WorldWideScience

Sample records for hybrid natural products

  1. Hybrid Natural Inflation

    Science.gov (United States)

    Ross, Graham G.; Germán, Gabriel; Vázquez, J. Alberto

    2016-05-01

    We construct two simple effective field theory versions of Hybrid Natural Inflation (HNI) that illustrate the range of its phenomenological implications. The resulting inflationary sector potential, V = Δ4(1 + acos( ϕ/f)), arises naturally, with the inflaton field a pseudo-Nambu-Goldstone boson. The end of inflation is triggered by a waterfall field and the conditions for this to happen are determined. Also of interest is the fact that the slow-roll parameter ɛ (and hence the tensor r) is a non-monotonic function of the field with a maximum where observables take universal values that determines the maximum possible tensor to scalar ratio r. In one of the models the inflationary scale can be as low as the electroweak scale. We explore in detail the associated HNI phenomenology, taking account of the constraints from Black Hole production, and perform a detailed fit to the Planck 2015 temperature and polarisation data.

  2. Biocombinatorial Engineering of Fungal PKS-NRPS Hybrids for Production of Novel Synthetic Natural Products

    DEFF Research Database (Denmark)

    Nielsen, Maria Lund

    . Secondary metabolites (SMs) from bacteria, plants and filamentous fungi constitute a large group of important natural products. In this thesis I explore the biosynthesis of several fungal SMs along with the enzymes responsible for their synthesis. Specifically, my research focuses on the expression...... and engineering of a certain type of fungal enzymes – natural fusions of polyketide synthases and nonribosomal peptide synthetases (PKS-NRPSs). The thesis is divided into two topics: 1) Expanding fungal chemodiversity through combinatorial biosynthesis 2) Two CRISPR-Cas9-based approaches to linking SMs...... and NRPS modules. In the third study (chapter 4), I describe how CRISPR-Cas9, which was recently implemented for genome editing in filamentous fungi, can be used to link SMs to their genetic origin in a fungus where no genetic tools were previously available. Using CRISPR-Cas9, I identified a novel gene...

  3. Techno-economic analysis of biomethanol production via hybrid steam reforming of glycerol with natural gas

    NARCIS (Netherlands)

    Balegedde Ramachandran, P.; Oudenhoven, S.R.G; Kersten, S.R.A.; Rossum, van G.; Ham, van der A.G.J.

    2013-01-01

    The present article deals with the techno-economic assessment of the hybrid steam reforming (HSR) process of glycerol (obtained via transesterification) together with natural gas to produce biomethanol via the synthesis gas route. In this techno-economic assessment, a model is developed in the UniSi

  4. A natural product inspired hybrid approach towards the synthesis of novel pentamidine based scaffolds as potential anti-parasitic agents.

    Science.gov (United States)

    Tyagi, Vikas; Khan, Shahnawaz; Shivahare, Rahul; Srivastava, Khushboo; Gupta, Suman; Kidwai, Saqib; Srivastava, Kumkum; Puri, S K; Chauhan, Prem M S

    2013-01-01

    A natural product inspired molecular hybridization approach led us to a series of novel pentamidine based pyrimidine and chalcone scaffolds. All the hybrids were evaluated for their anti-leishmanial potential. Most of the screened compounds have showed significant in vitro anti-leishmanial activity with less cytotoxicity in comparison to the standard drugs (pentamidine, sodium stibogluconate, and miltefosine). Additionally, anti-malarial screening of these compounds was also done and four compounds have shown superior activity against chloroquine resistance strain (K1) of Plasmodium falciparum.

  5. Total synthesis of a potent hybrid of the anticancer natural products dictyostatin and discodermolide.

    Science.gov (United States)

    Paterson, Ian; Naylor, Guy J; Wright, Amy E

    2008-10-14

    A potent dictyostatin-discodermolide hybrid was designed and synthesised; it showed enhanced cell growth inhibitory activity relative to discodermolide in four human cancer cell lines including the Taxol-resistant NCI/ADR-Res cell line.

  6. Synthesis gas production via hybrid steam reforming of natural gas and bio-liquids

    NARCIS (Netherlands)

    Balegedde Ramachandran, P.

    2013-01-01

    This thesis deals with (catalytic) steam reforming of bio-liquids for the production of synthesis gas. Glycerol, both crude from the biodiesel manufacturing and refined, and pyrolysis oil are tested as bio-based feedstocks. Liquid bio-based feeds could be preferred over inhomogeneous fibrous solid b

  7. Combinatorial synthesis of natural products

    DEFF Research Database (Denmark)

    Nielsen, John

    2002-01-01

    for preparation of combinatorial libraries. In other examples, natural products or intermediates have served as building blocks or scaffolds in the synthesis of complex natural products, bioactive analogues or designed hybrid molecules. Finally, structural motifs from the biologically active parent molecule have......Combinatorial syntheses allow production of compound libraries in an expeditious and organized manner immediately applicable for high-throughput screening. Natural products possess a pedigree to justify quality and appreciation in drug discovery and development. Currently, we are seeing a rapid...

  8. Total synthesis and biological evaluation of a series of macrocyclic hybrids and analogues of the antimitotic natural products dictyostatin, discodermolide, and taxol.

    Science.gov (United States)

    Paterson, Ian; Naylor, Guy J; Gardner, Nicola M; Guzmán, Esther; Wright, Amy E

    2011-02-01

    The design, synthesis, and biological evaluation of a series of hybrids and analogues of the microtubule-stabilizing anticancer agents dictyostatin, discodermolide, and taxol is described. A 22-membered macrolide scaffold was prepared by adapting earlier synthetic routes directed towards dictyostatin and discodermolide, taking advantage of the distinctive structural and stereochemical similarities between these two polyketide-derived marine natural products. Initial endeavors towards accessing novel discodermolide/dictyostatin hybrids led to the adoption of a late-stage diversification strategy and the construction of a small library of methyl-ether derivatives, along with the first triple hybrids bearing the side-chain of taxol or taxotere attached through an ester linkage. Biological assays of the anti-proliferative activity of these compounds in a series of human cancer cell lines, including the taxol-resistant NCI/ADR-Res cell line, allowed the proposal of various structure-activity relationships. This led to the identification of a potent macrocyclic discodermolide/dictyostatin hybrid 12 and its C9 methoxy derivative 38, accessible by an efficient total synthesis and with a similar biological profile to dictyostatin.

  9. Design Principles for Natural and Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per

    For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system- Hybrid Ventilation....... The hybrid ventilation concepts, design challenges and principles are discussed and illustrated by four building examples....

  10. Synthesis and preliminary biological evaluation of a small library of hybrid compounds based on Ugi isocyanide multicomponent reactions with a marine natural product scaffold.

    Science.gov (United States)

    Avilés, Edward; Prudhomme, Jacques; Le Roch, Karine G; Franzblau, Scott G; Chandrasena, Kevin; Mayer, Alejandro M S; Rodríguez, Abimael D

    2015-11-15

    A mixture-based combinatorial library of five Ugi adducts (4-8) incorporating known antitubercular and antimalarial pharmacophores was successfully synthesized, starting from the naturally occurring diisocyanide 3, via parallel Ugi four-center three-component reactions (U-4C-3CR). The novel α-acylamino amides obtained were evaluated for their antiinfective potential against laboratory strains of Mycobacterium tuberculosis H37Rv and chloroquine-susceptible 3D7 Plasmodium falciparum. Interestingly, compounds 4-8 displayed potent in vitro antiparasitic activity with higher cytotoxicity in comparison to their diisocyanide precursor 3, with the best compound exhibiting an IC50 value of 3.6 nM. Additionally, these natural product inspired hybrids potently inhibited in vitro thromboxane B2 (TXB2) and superoxide anion (O2(-)) generation from Escherichia coli lipopolysaccharide (LPS)-activated rat neonatal microglia, with concomitant low short-term toxicity.

  11. Natural hybridization and introgression in sympatric Ligularia species (Asteraceae, Senecioneae)

    Institute of Scientific and Technical Information of China (English)

    Jiao-Jun YU; Chiaki KURODA; Xun GONG

    2011-01-01

    The difficulty in clarifying species of genus Ligularia Cass.has been attributed to rapid and continuous allopatric speciation in small and isolated populations,combined with interspecific diploid hybridization in the Qinghai-Tibetan Plateau and adjacent areas.However,no concrete example has been reported to prove this hypothesis.We studied a natural mixed population of six species of Ligularia in which some individuals were morphologically intermediate between L.subspicata and L.nelumbifolia.Based on DNA sequences (trnC-E trnL-rpL32,trnQ5'rpsl6,trnK-rpsl6,and internal transcribed spacer) and inter-simple sequence repeat data,we concluded that putative hybrids are primarily products of hybridization between L.nelumbifolia and L.subspicata.The other four species or additional,unknown species may also be involved in hybridization.This hybridization is bidirectional but asymmetrical.Hybrid individuals were mostly the first generation,but F2 and later-generation hybrids were also present.Moreover,the backcrossed individuals detected indicate that natural gene flow occurs among at least three Ligularia species.Hybrids may become stabilized to form new species or may function as intermediates in evolutionary diversification.

  12. Antiplasmodial Natural Products

    Directory of Open Access Journals (Sweden)

    Cláudio R. Nogueira

    2011-03-01

    Full Text Available Malaria is a human infectious disease that is caused by four species of Plasmodium. It is responsible for more than 1 million deaths per year. Natural products contain a great variety of chemical structures and have been screened for antiplasmodial activity as potential sources of new antimalarial drugs. This review highlights studies on natural products with antimalarial and antiplasmodial activity reported in the literature from January 2009 to November 2010. A total of 360 antiplasmodial natural products comprised of terpenes, including iridoids, sesquiterpenes, diterpenes, terpenoid benzoquinones, steroids, quassinoids, limonoids, curcubitacins, and lanostanes; flavonoids; alkaloids; peptides; phenylalkanoids; xanthones; naphthopyrones; polyketides, including halenaquinones, peroxides, polyacetylenes, and resorcylic acids; depsidones; benzophenones; macrolides; and miscellaneous compounds, including halogenated compounds and chromenes are listed in this review.

  13. Natural Products for Antithrombosis

    Directory of Open Access Journals (Sweden)

    Cen Chen

    2015-01-01

    Full Text Available Thrombosis is considered to be closely related to several diseases such as atherosclerosis, ischemic heart disease and stroke, as well as rheumatoid arthritis, hyperuricemia, and various inflammatory conditions. More and more studies have been focused on understanding the mechanism of molecular and cellular basis of thrombus formation as well as preventing thrombosis for the treatment of thrombotic diseases. In reality, there is considerable interest in the role of natural products and their bioactive components in the prevention and treatment of thrombosis related disorders. This paper briefly describes the mechanisms of thrombus formation on three aspects, including coagulation system, platelet activation, and aggregation, and change of blood flow conditions. Furthermore, the natural products for antithrombosis by anticoagulation, antiplatelet aggregation, and fibrinolysis were summarized, respectively.

  14. Stereoselective Halogenation in Natural Product Synthesis.

    Science.gov (United States)

    Chung, Won-jin; Vanderwal, Christopher D

    2016-03-24

    At last count, nearly 5000 halogenated natural products have been discovered. In approximately half of these compounds, the carbon atom to which the halogen is bound is sp(3) -hybridized; therefore, there are an enormous number of natural products for which stereocontrolled halogenation must be a critical component of any synthesis strategy. In this Review, we critically discuss the methods and strategies used for stereoselective introduction of halogen atoms in the context of natural product synthesis. Using the successes of the past, we also attempt to identify gaps in our synthesis technology that would aid the synthesis of halogenated natural products, as well as existing methods that have not yet seen application in complex molecule synthesis. The chemistry described herein demonstrates yet again how natural products continue to provide the inspiration for critical advances in chemical synthesis.

  15. Hybrid Organization of Production and Distribution

    Directory of Open Access Journals (Sweden)

    Claude Menard

    2006-03-01

    Full Text Available This paper emphasizes the central role of arrangements called “hybrids” in the organization of production and distribution in market economies. Several forms are taken into account, such as subcontracting, supply-chain systems, distribution networks, franchising, partnerships, alliances, or cooperatives. It is argued that under the apparent heterogeneity of these forms are shared characteristics qualifying them as specific “institutional structures of production”. The paper stresses that beyond their relevance for economists wishing to understand the coexistence of alternative modes of governance in market economies, hybrid arrangements provide unique opportunities for theoretical investigation on the nature of inter-firm coordination.

  16. Modelling of Natural and Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per

    be installed in existing buildings after a few modifications. In contrast, ventilation systems using only natural forces such as wind and thermal buoyancy need to be designed together with the building, since the building itself and its components are the elements that can reduce or increase air movement...... as well as influence the air content (dust, pollution etc.). Architects and engineers need to acquire qualitative and quantitative information about the interactions between building characteristics and natural ventilation in order to design buildings and systems consistent with a passive low......-energy approach. These lecture notes focus on modelling of natural and hybrid ventilation driven by thermal buoyancy, wind and/or mechanical driving forces for a single zone with one, two or several openings....

  17. Testing hybrid natural inflation with BICEP2

    Energy Technology Data Exchange (ETDEWEB)

    Carrillo-González, Mariana [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Apdo. Postal 48-3, 62251 Cuernavaca, Morelos (Mexico); Germán, Gabriel, E-mail: gabriel@fis.unam.mx [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Apdo. Postal 48-3, 62251 Cuernavaca, Morelos (Mexico); Herrera-Aguilar, Alfredo [Departamento de Física, Universidad Autónoma Metropolitana Iztapalapa, San Rafael Atlixco 186, CP 09340, México D.F. (Mexico); Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo, Edificio C-3, Ciudad Universitaria, CP 58040, Morelia, Michoacán (Mexico); Hidalgo, Juan Carlos [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Apdo. Postal 48-3, 62251 Cuernavaca, Morelos (Mexico); Sussman, Roberto A. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apdo. Postal 70-543, 04510 México D.F. (Mexico)

    2014-06-27

    We analyse Hybrid Natural Inflation in view of the recent results for the tensor index reported by BICEP2. We find that it predicts a large running of the scalar spectrum which is potentially detectable by large scale structure through measurements of clustering of galaxies in combination with CMB data and by 21 cm forest observations. The running of the running is also relatively large becoming close to 10{sup −2}. Along the way, we find general consistency relations at which observables are subject if the slow-roll approximation is imposed. Failure to satisfy these equations by the values obtained for the observables in surveys would be a failure of the slow-roll approximation itself.

  18. Marine Natural Products Against Tuberculosis

    Directory of Open Access Journals (Sweden)

    Marcus Vinícius Nora De Souza

    2006-01-01

    Full Text Available Natural products represent an outstanding source of compounds that play an important role in the treatment of human diseases. Due to the importance of nature as a source of new drug candidates, the aim of this review is to highlight the marine natural products, which exhibit antituberculosis activity, discovered between 2000 and 2005.

  19. Natural hybrid organic-inorganic photovoltaic devices

    Science.gov (United States)

    De Padova, Paola; Lucci, Massimiliano; Olivieri, Bruno; Quaresima, Claudio; Priori, Sandro; Francini, Roberto; Grilli, Antonio; Hricovini, Karol; Davoli, Ivan

    2009-06-01

    Natural hybrid organic-inorganic photovoltaic devices based on TiO 2 have been realized. Chlorophyll A (from anacystis nidulans algae), chlorophyll B (from spinach), carmic acid (from insect Coccus cacti L.), synthetic trans- β-carotene, natural fresh picked Morus nigra, and their mixtures have been used as an organic photo active layer to fabricate photovoltaic prototypes. In order to reduce the charge's interfacial recombination, different thicknesses (5-45 nm) of Si layers, subsequently oxidized in air, were inserted between the TiO 2 and chlorophyll B. Scanning electron microscopy of TiO 2 and Si/TiO 2 systems shows the coexistence at least of four classes of nanoparticles of 60, 100, 150 and 250 nm in size. Auger electron spectroscopy of the Si L 2,3V V transition demonstrates the presence of silica and SiO x suboxides. Photocurrent measurements versus radiation wavelength in the range 300-800 nm exhibit different peaks according to the absorption spectra of the organic molecules. All realized photovoltaic devices are suitable for solar light electric energy conversion. Those made of a blend of all organic molecules achieved higher current and voltage output. The Si/TiO 2-based devices containing chlorophyll B exhibited an enhanced photocurrent response with respect to those with TiO 2 only.

  20. The hebridological analysis of productivity traits in pea hybrids

    Directory of Open Access Journals (Sweden)

    Світлана Володимирівна Коблай

    2015-09-01

    Full Text Available To study the nature of inheritance of quantitative traits that influence productivity of pea hybrids were obtained first and second generations for which sample and varieties with different leaf morphotype are served as parental form. As the results of hybridological analysis it is determined the degree of domination and revealed the heterosis combinations

  1. A Hybrid Architecture For Natural Language Understanding

    Science.gov (United States)

    Loatman, R. Bruce

    1987-05-01

    The PRC Adaptive Knowledge-based Text Understanding System (PAKTUS) is an environment for developing natural language understanding (NLU) systems. It uses a knowledge-based approach in an integrated hybrid architecture based on a factoring of the NLU problem into its lexi-cal, syntactic, conceptual, domain-specific, and pragmatic components. The goal is a robust system that benefits from the strengths of several NLU methodologies, each applied where most appropriate. PAKTUS employs a frame-based knowledge representation and associative networks throughout. The lexical component uses morphological knowledge and word experts. Syntactic knowledge is represented in an Augmented Transition Network (ATN) grammar that incorporates rule-based programming. Case grammar is used for canonical conceptual representation with constraints. Domain-specific templates represent knowledge about specific applications as patterns of the form used in logic programming. Pragmatic knowledge may augment any of the other types and is added wherever needed for a particular domain. The system has been constructed in an interactive graphic programming environment. It has been used successfully to build a prototype front end for an expert system. This integration of existing technologies makes limited but practical NLU feasible now for narrow, well-defined domains.

  2. Methane production in simulated hybrid bioreactor landfill.

    Science.gov (United States)

    Xu, Qiyong; Jin, Xiao; Ma, Zeyu; Tao, Huchun; Ko, Jae Hac

    2014-09-01

    The aim of this work was to study a hybrid bioreactor landfill technology for landfill methane production from municipal solid waste. Two laboratory-scale columns were operated for about ten months to simulate an anaerobic and a hybrid landfill bioreactor, respectively. Leachate was recirculated into each column but aeration was conducted in the hybrid bioreactor during the first stage. Results showed that leachate pH in the anaerobic bioreactor maintained below 6.5, while in the hybrid bioreactor quickly increased from 5.6 to 7.0 due to the aeration. The temporary aeration resulted in lowering COD and BOD5 in the leachate. The volume of methane collected from the hybrid bioreactor was 400 times greater than that of the anaerobic bioreactor. Also, the methane production rate of the hybrid bioreactor was improved within a short period of time. After about 10 months' operation, the total methane production in the hybrid bioreactor was 212 L (16 L/kgwaste).

  3. Hybrid isoprenoid secondary metabolite production in terrestrial and marine actinomycetes.

    Science.gov (United States)

    Gallagher, Kelley A; Fenical, William; Jensen, Paul R

    2010-12-01

    Terpenoids are among the most ubiquitous and diverse secondary metabolites observed in nature. Although actinomycete bacteria are one of the primary sources of microbially derived secondary metabolites, they rarely produce compounds in this biosynthetic class. The terpenoid secondary metabolites that have been discovered from actinomycetes are often in the form of biosynthetic hybrids called hybrid isoprenoids (HIs). HIs include significant structural diversity and biological activity and thus are important targets for natural product discovery. Recent screening of marine actinomycetes has led to the discovery of a new lineage that is enriched in the production of biologically active HI secondary metabolites. These strains represent a promising resource for natural product discovery and provide unique opportunities to study the evolutionary history and ecological functions of an unusual group of secondary metabolites. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Natural products for plant protection

    Directory of Open Access Journals (Sweden)

    Čeković Živorad

    2006-01-01

    Full Text Available The advantage applying natural products, such as a secondary metabolites, in plant protection is shortly presented. Acceptable solutions for the enhanced ecological criteria, which are requested by the users of pesticides and consumers of agricultural goods, could be the replacement of classical pesticides by natural products in plant protection. Some natural products are already in use as insecticides, herbicides and fungicides because new biotechnological processes, fermentation and biotransformations provide procedures for their industrial production. In addition to biotechnical processes natural compounds possessing pesticide activities are also prepared by chemical synthesis. An active secondary metabolite must first be isolated from natural sauces and then, based on biological toxicological and ecological studies, acceptable compounds are selected for laboratory and industrial chemical synthesis. Several compounds possessing insecticidal, herbicidal and fungicidal activities, which have been successfully applied for plan protection are presented.

  5. Hybrid reactors: Nuclear breeding or energy production?

    Energy Technology Data Exchange (ETDEWEB)

    Piera, Mireia [UNED, ETSII-Dp Ingenieria Energetica, c/Juan del Rosal 12, 28040 Madrid (Spain); Lafuente, Antonio; Abanades, Alberto; Martinez-Val, J.M. [ETSII-UPM, c/Jose Gutierrez Abascal 2, 28006 Madrid (Spain)

    2010-09-15

    After reviewing the long-standing tradition on hybrid research, an assessment model is presented in order to characterize the hybrid performance under different objectives. In hybrids, neutron multiplication in the subcritical blanket plays a major role, not only for energy production and nuclear breeding, but also for tritium breeding, which is fundamental requirement in fusion-fission hybrids. All three objectives are better achieved with high values of the neutron multiplication factor (k-eff) with the obvious and fundamental limitation that it cannot reach criticality under any event, particularly, in the case of a loss of coolant accident. This limitation will be very important in the selection of the coolant. Some general considerations will be proposed, as guidelines for assessing the hybrid potential in a given scenario. Those guidelines point out that hybrids can be of great interest for the future of nuclear energy in a framework of Sustainable Development, because they can contribute to the efficient exploitation of nuclear fuels, with very high safety features. Additionally, a proposal is presented on a blanket specially suited for fusion-fission hybrids, although this reactor concept is still under review, and new work is needed for identifying the most suitable blanket composition, which can vary depending on the main objective of the hybrid. (author)

  6. Hybrid simulation models of production networks

    CERN Document Server

    Kouikoglou, Vassilis S

    2001-01-01

    This book is concerned with a most important area of industrial production, that of analysis and optimization of production lines and networks using discrete-event models and simulation. The book introduces a novel approach that combines analytic models and discrete-event simulation. Unlike conventional piece-by-piece simulation, this method observes a reduced number of events between which the evolution of the system is tracked analytically. Using this hybrid approach, several models are developed for the analysis of production lines and networks. The hybrid approach combines speed and accuracy for exceptional analysis of most practical situations. A number of optimization problems, involving buffer design, workforce planning, and production control, are solved through the use of hybrid models.

  7. Split-gene system for hybrid wheat seed production.

    Science.gov (United States)

    Kempe, Katja; Rubtsova, Myroslava; Gils, Mario

    2014-06-24

    Hybrid wheat plants are superior in yield and growth characteristics compared with their homozygous parents. The commercial production of wheat hybrids is difficult because of the inbreeding nature of wheat and the lack of a practical fertility control that enforces outcrossing. We describe a hybrid wheat system that relies on the expression of a phytotoxic barnase and provides for male sterility. The barnase coding information is divided and distributed at two loci that are located on allelic positions of the host chromosome and are therefore "linked in repulsion." Functional complementation of the loci is achieved through coexpression of the barnase fragments and intein-mediated ligation of the barnase protein fragments. This system allows for growth and maintenance of male-sterile female crossing partners, whereas the hybrids are fertile. The technology does not require fertility restorers and is based solely on the genetic modification of the female crossing partner.

  8. Natural products in chemical biology

    National Research Council Canada - National Science Library

    Civjan, Natanya

    2012-01-01

    "Based on the award winning Wiley Encyclopedia of Chemical Biology, this book provides a general overview of the unique features of the small molecules referred to as "natural products", explores how...

  9. PRODUCTION VALUES OF INVESTIGATED SUGAR BEET HYBRIDS

    Directory of Open Access Journals (Sweden)

    M. Pospišil

    2006-06-01

    Full Text Available Production values of 43 experimental and recognized sugar beet hybrids were conducted on the Zagreb location in the period 2003-2005. The trials included hybrids from six breeding institutions that sell sugar beet seed in the Republic of Croatia. Research results have revealed significant differences in yields and root quality among inve- stigated sugar beet hybrids. However, the results of a large number of hybrids were equal in value; namely, the dif- ference between them was within the statistically allowable deviation. The hybrids KW 0148 HR and Buda in 2003, Sofarizo and Takt were distinguished by high sugar yields in 2004, whereas Merak, Impact and Europa in 2005. The highest root yields were recorded for hybrids Dioneta, Buda and KW 0148 HR in 2003, Sofarizo, Takt, HI 0191 and Dorotea in 2004, Impact and SES 2371 in 2005. The highest root sugar contents were determined in hybrids Zita and Evelina in 2003, Cyntia, Diamant and Belinda in 2004, and Merak, Belinda and Cyntia in 2005.

  10. Combinatorial synthesis of natural products

    DEFF Research Database (Denmark)

    Nielsen, John

    2002-01-01

    Combinatorial syntheses allow production of compound libraries in an expeditious and organized manner immediately applicable for high-throughput screening. Natural products possess a pedigree to justify quality and appreciation in drug discovery and development. Currently, we are seeing a rapid...

  11. Molecular Characterization of New Natural Hybrids of Saccharomyces cerevisiae and S. kudriavzevii in Brewing▿ †

    Science.gov (United States)

    González, Sara S.; Barrio, Eladio; Querol, Amparo

    2008-01-01

    We analyzed 24 beer strains from different origins by using PCR-restriction fragment length polymorphism analysis of different gene regions, and six new Saccharomyces cerevisiae × Saccharomyces kudriavzevii hybrid strains were found. This is the first time that the presence in brewing of this new type of hybrid has been demonstrated. From the comparative molecular analysis of these natural hybrids with respect to those described in wines, it can be concluded that these originated from at least two hybridization events and that some brewing hybrids share a common origin with wine hybrids. Finally, a reduction of the S. kudriavzevii fraction of the hybrid genomes was observed, but this reduction was found to vary among hybrids regardless of the source of isolation. The fact that 25% of the strains analyzed were discovered to be S. cerevisiae × S. kudriavzevii hybrids suggests that an important fraction of brewing strains classified as S. cerevisiae may correspond to hybrids, contributing to the complexity of Saccharomyces diversity in brewing environments. The present study raises new questions about the prevalence of these new hybrids in brewing as well as their contribution to the properties of the final product. PMID:18296532

  12. Molecular characterization of new natural hybrids of Saccharomyces cerevisiae and S. kudriavzevii in brewing.

    Science.gov (United States)

    González, Sara S; Barrio, Eladio; Querol, Amparo

    2008-04-01

    We analyzed 24 beer strains from different origins by using PCR-restriction fragment length polymorphism analysis of different gene regions, and six new Saccharomyces cerevisiae x Saccharomyces kudriavzevii hybrid strains were found. This is the first time that the presence in brewing of this new type of hybrid has been demonstrated. From the comparative molecular analysis of these natural hybrids with respect to those described in wines, it can be concluded that these originated from at least two hybridization events and that some brewing hybrids share a common origin with wine hybrids. Finally, a reduction of the S. kudriavzevii fraction of the hybrid genomes was observed, but this reduction was found to vary among hybrids regardless of the source of isolation. The fact that 25% of the strains analyzed were discovered to be S. cerevisiae x S. kudriavzevii hybrids suggests that an important fraction of brewing strains classified as S. cerevisiae may correspond to hybrids, contributing to the complexity of Saccharomyces diversity in brewing environments. The present study raises new questions about the prevalence of these new hybrids in brewing as well as their contribution to the properties of the final product.

  13. Synthesis of Polycyclic Natural Products

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Tuan Hoang [Iowa State Univ., Ames, IA (United States)

    2003-01-01

    With the continuous advancements in molecular biology and modern medicine, organic synthesis has become vital to the support and extension of those discoveries. The isolations of new natural products allow for the understanding of their biological activities and therapeutic value. Organic synthesis is employed to aid in the determination of the relationship between structure and function of these natural products. The development of synthetic methodologies in the course of total syntheses is imperative for the expansion of this highly interdisciplinary field of science. In addition to the practical applications of total syntheses, the structural complexity of natural products represents a worthwhile challenge in itself. The pursuit of concise and efficient syntheses of complex molecules is both gratifying and enjoyable.

  14. Synthesis of Polycyclic Natural Products

    Energy Technology Data Exchange (ETDEWEB)

    Tuan Hoang Nguyen

    2003-05-31

    With the continuous advancements in molecular biology and modern medicine, organic synthesis has become vital to the support and extension of those discoveries. The isolations of new natural products allow for the understanding of their biological activities and therapeutic value. Organic synthesis is employed to aid in the determination of the relationship between structure and function of these natural products. The development of synthetic methodologies in the course of total syntheses is imperative for the expansion of this highly interdisciplinary field of science. In addition to the practical applications of total syntheses, the structural complexity of natural products represents a worthwhile challenge in itself. The pursuit of concise and efficient syntheses of complex molecules is both gratifying and enjoyable.

  15. Mechanical behavior of glass fiber polyester hybrid composite filled with natural fillers

    Science.gov (United States)

    Gupta, G.; Gupta, A.; Dhanola, A.; Raturi, A.

    2016-09-01

    Now-a-days, the natural fibers and fillers from renewable natural resources offer the potential to act as a reinforcing material for polymer composite material alternative to the use of synthetic fiber like as; glass, carbon and other man-made fibers. Among various natural fibers and fillers like banana, wheat straw, rice husk, wood powder, sisal, jute, hemp etc. are the most widely used natural fibers and fillers due to its advantages like easy availability, low density, low production cost and reasonable physical and mechanical properties This research work presents the effect of natural fillers loading with 5%, 10% and 15% on mechanical behavior of polyester based hybrid composites. The result of test depicted that hybrid composite has far better properties than single fibre glass reinforced composite under impact and flexural loads. However it is found that the hybrid composite have better strength as compared to single glass fibre composites.

  16. The Nature of Society: Enmapping Nature, Space and Society into a Town-green Hybrid

    Directory of Open Access Journals (Sweden)

    Louis Rice

    2014-10-01

    Full Text Available The paper describes the transformation of derelict land into a 'town-green' and the role legislation played in transforming social and natural relationships. Town-green denotes a legal status under the Great Britain Commons Act (2006 that protects certain open spaces from building development; the status requires that a space must simultaneously have a specific social quality (i.e. 'town-ness' and a specific natural quality (i.e. 'green-ness'. This hybrid condition requires an alliance between society and nature in a certain configuration (referred to here as nature2 and society2. In this empirical study it involved the participation and consensus of local residents, volunteer gardeners as well as nature itself; flowers needed to bloom and grass had to grow in order for the hybrid town-green status to be conferred. There are two distinct phases of this transformation; the first is the change in identities and configuration of the constituents of town and green. This involved the production of a modified 'real' world with: different plants and flowers; reconfigured spatial arrangements; as well as different social actors. The second phase is a shift from changes in the "real" world towards an 'enmap' - a displacement of myriad actors into documentation. This transfer from a complex messy reality into an enmap permitted the legitimation of the new network to be accepted as a 'town-green'. What the research reveals, other than hints for gardeners and community activists, is how material and non-material; social and natural; spatial, discursive and temporal worlds are hybridised.

  17. Natural Products from Mangrove Actinomycetes

    Directory of Open Access Journals (Sweden)

    Dong-Bo Xu

    2014-05-01

    Full Text Available Mangroves are woody plants located in tropical and subtropical intertidal coastal regions. The mangrove ecosystem is becoming a hot spot for natural product discovery and bioactivity survey. Diverse mangrove actinomycetes as promising and productive sources are worth being explored and uncovered. At the time of writing, we report 73 novel compounds and 49 known compounds isolated from mangrove actinomycetes including alkaloids, benzene derivatives, cyclopentenone derivatives, dilactones, macrolides, 2-pyranones and sesquiterpenes. Attractive structures such as salinosporamides, xiamycins and novel indolocarbazoles are highlighted. Many exciting compounds have been proven as potential new antibiotics, antitumor and antiviral agents, anti-fibrotic agents and antioxidants. Furthermore, some of their biosynthetic pathways have also been revealed. This review is an attempt to consolidate and summarize the past and the latest studies on mangrove actinomycetes natural product discovery and to draw attention to their immense potential as novel and bioactive compounds for marine drugs discovery.

  18. Design of Natural and Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per

    -energy approach. Natural ventilation can be used to provide fresh air for the occupants, necessary to maintain acceptable air quality levels, and to cool buildings in cases where the climatic conditions allow it. Natural ventilation is caused by pressure differences at the inlets and outlets of a building......The effectiveness of natural ventilation, i.e. its ability to ensure indoor air quality and passive cooling in a building, depends greatly on the design process. Mechanical ventilation systems can be designed separately from the design of the building in which they are installed. They can also...... be installed in existing buildings after a few modifications. In contrast, ventilation systems using only natural forces such as wind and thermal buoyancy need to be designed together with the building, since the building itself and its components are the elements that can reduce or increase air movement...

  19. System of Natural Health Products

    Directory of Open Access Journals (Sweden)

    Angelica Paoletti

    2011-01-01

    Full Text Available Introduction. The safety of vitamin K antagonists (VKA use can be compromised by many popular herbal supplements taken by individuals. The literature reports that 30% of warfarin-treated patients self-medicates with herbs. Possible interactions represent an health risk. We aimed to identify all herbs-oral anticoagulants interactions collected in the Italian database of suspected adverse reactions to “natural health” products. Methods. The Italian database of spontaneous reports of suspected adverse reactions to natural products was analyzed to address herb-VKAs interactions. Results. From 2002 to 2009, we identified 12 reports with 7 cases of INR reduction in patients treated with warfarin (n=3 and acenocoumarol (n=4, and 5 cases of INR increase (all warfarin associated. It was reported 8 different herbal products as possibly interacting. Discussion. Our study confirms the risk of interactions, highlighting the difficulty to characterize them and their mechanisms and, finally, prevent their onset. The reported data underline the urgent need of healthcare providers being aware of the possible interaction between natural products and VKA, also because of the critical clinical conditions affecting patients. This is the first step to have the best approach to understand possible INR alterations linked to herb-VKA interaction and to rightly educate patients in treatment with VKA.

  20. Transference and natural gas distribution system analysis utilizing hybrid modelling; Analise de sistemas de transferencia e distribuicao de gas natural utilizando modelagem hibrida

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, Robson A.; Martinkoski, Ricardo [Centro Federal de Educacao Tecnologica do Parana (CEFET), Curitiba, PR (Brazil); Neves Junior, Flavio [Centro Federal de Educacao Tecnologica do Parana (CEFET), Curitiba, PR (Brazil). Programa de Pos-Graduacao em Engenharia Eletrica e Informatica Industrial

    2003-07-01

    The objective of this article is to apply techniques of formal specification in modelling of natural gas transmission and distribution systems. In this case the formal models are characterized by using hybrid automata. Initially the existent components in the net are modeled and represented by independent hybrid automata. The global dynamics is obtained through the product hybrid automata. Languages representing the desirable states of the system are obtained from the hybrid automata, allowing a hybrid control procedure. An automatic tool as SHIFT must be used to modelling and simulation. (author)

  1. Hybrid Lanczos-type product methods

    Energy Technology Data Exchange (ETDEWEB)

    Ressel, K.J. [Swiss Center for Scientific Computing, Zuerich (Switzerland)

    1996-12-31

    A general framework is proposed to construct hybrid iterative methods for the solution of large nonsymmetric systems of linear equations. This framework is based on Lanczos-type product methods, whose iteration polynomial consists of the Lanczos polynomial multiplied by some other arbitrary, {open_quotes}shadow{close_quotes} polynomial. By using for the shadow polynomial Chebyshev (more general Faber) polynomials or L{sup 2}-optimal polynomials, hybrid (Chebyshev-like) methods are incorporated into Lanczos-type product methods. In addition, to acquire spectral information on the system matrix, which is required for such a choice of shadow polynomials, the Lanczos-process can be employed either directly or in an QMR-like approach. The QMR like approach allows the cheap computation of the roots of the B-orthogonal polynomials and the residual polynomials associated with the QMR iteration. These roots can be used as a good approximation for the spectrum of the system matrix. Different choices for the shadow polynomials and their construction are analyzed. The resulting hybrid methods are compared with standard Lanczos-type product methods, like BiOStab, BiOStab({ell}) and BiOS.

  2. Glycosylation and Activities of Natural Products.

    Science.gov (United States)

    Huang, Gangliang; Lv, Meijiao; Hu, Jinchuan; Huang, Kunlin; Xu, Hong

    2016-01-01

    Natural products are widely found in nature, their number and variety are numerous, the structures are complex and diverse. These natural products have many physiological and pharmacological activities. Glycosylation can increase the diversity of structure and function of natural product, it has become the focus of drug research and development. The impacts of glycosylation of natural products to water solubility, pharmacological activities, bioavailability, or others were described in this review, which provides a reference for the development and application of glycosylated natural products.

  3. Achieving Natural and Hybrid Ventilation in Practice

    DEFF Research Database (Denmark)

    Liddament, Martin; Axley, James; Heiselberg, Per

    2006-01-01

    Case studies provide essential evidence about the performance of buildings. They also illustrate the methods by which a technology can be implemented as well as highlighting problems. Various case study buildings (both new and retrofit) that incorporate mixed mode, natural ventilation and low ene...

  4. Natural products as antimitotic agents.

    Science.gov (United States)

    Dall'Acqua, Stefano

    2014-01-01

    Natural products still play an important role in the medicinal chemistry, especially in some therapeutic areas. As example more than 60% of currently-used anticancer agents are derives from natural sources including plants, marine organisms or micro-organism. Thus natural products (NP) are an high-impact source of new "lead compounds" or new potential therapeutic agents despite the large development of biotechnology and combinatorial chemistry in the drug discovery and development. Many examples of anticancer drugs as paclitaxel, combretastatin, bryostatin and discodermolide have shown the importance of NP in the anticancer chemotherapy through many years. Many organisms have been studied as sources of drugs namely plants, micro-organisms and marine organisms and the obtained NP can be considered a group of "privileged chemical structures" evolved in nature to interact with other organisms. For this reason NP are a good starting points for pharmaceutical research and also for library design. Tubulin and microtubules are one of the most studied targets for the search of anticancer compounds. Microtubule targeting agents (MTA) also named antimitotic agents are compounds that are able to perturb mitosis but are also able to arrest cell growing during interphase. The anticancer drugs, taxanes and vinca alkaloids have established tubulin as important target in cancer therapy. More recently the vascular disrupting agents (VDA) combretastatin analogues were studied for their antimitotics properties. This review will consider the anti mitotic NP and their potential impact in the development of new therapeutic agents.

  5. Cannibalism in single-batch hybrid catfish production ponds

    Science.gov (United States)

    Hybrid catfish are more efficiently harvested by seining than are Channel Catfish. Due to that, and their faster growth, hybrids are typically produced in “single-batch” production systems, either in intensively-aerated commercial ponds or in split-pond systems. In either production system, hybrids...

  6. Effects of natural hybrid and non-hybrid Epichloë endophytes on the response of Hordelymus europaeus to drought stress.

    Science.gov (United States)

    Oberhofer, Martina; Güsewell, Sabine; Leuchtmann, Adrian

    2014-01-01

    Interspecific hybrid endophytes of the genus Epichloë (Ascomycota, Clavicipitaceae) are prevalent in wild grass populations, possibly because of their larger gene variation, resulting in increased fitness benefits for host plants; however, the reasons are not yet known. We tested hypotheses regarding niche expansion mediated by hybrid endophytes, population-dependent interactions and local co-adaptation in the woodland grass Hordelymus europaeus, which naturally hosts both hybrid and non-hybrid endophyte taxa. Seedlings derived from seeds of four grass populations made endophyte free were re-inoculated with hybrid or non-hybrid endophyte strains, or left endophyte free. Plants were grown in the glasshouse with or without drought treatment. Endophyte infection increased plant biomass and tiller production by 10-15% in both treatments. Endophyte types had similar effects on growth, but opposite effects on reproduction: non-hybrid endophytes increased seed production, whereas hybrid endophytes reduced or prevented it completely. The results are consistent with the observation that non-hybrid endophytes in H. europaeus prevail at dry sites, but cannot explain the prevalence of hybrid endophytes. Thus, our results do not support the hypothesis of niche expansion of hybrid-infected plants. Moreover, plants inoculated with native relative to foreign endophytes yielded higher infections, but both showed similar growth and survival, suggesting weak co-adaptation.

  7. Natural Products Version 2.0: Connecting Genes to Molecules

    Science.gov (United States)

    Walsh, Christopher T.; Fischbach, Michael A.

    2009-01-01

    Natural products have played a prominent role in the history of organic chemistry, and they continue to be important as drugs, biological probes, and targets of study for synthetic and analytical chemists. In this perspective, we explore how connecting Nature’s small molecules to the genes that encode them has sparked a renaissance in natural product research, focusing primarily on the biosynthesis of polyketides and nonribosomal peptides. We survey monomer biogenesis, coupling chemistries from templated and non-templated pathways, and the broad set of tailoring reactions and hybrid pathways that give rise to the diverse scaffolds and functionalization patterns of natural products. We conclude by considering two questions: What would it take to find all natural product scaffolds? What kind of scientists will be studying natural products in the future? PMID:20121095

  8. Genetic Instability of Heterozygous, Hybrid, Natural Wine Yeasts

    Science.gov (United States)

    Ramírez, Manuel; Vinagre, Antonia; Ambrona, Jesús; Molina, Felipe; Maqueda, Matilde; Rebollo, JoséE.

    2004-01-01

    We describe a genetic instability found in natural wine yeasts but not in the common laboratory strains of Saccharomyces cerevisiae. Spontaneous cyh2R/cyh2R mutants resistant to high levels of cycloheximide can be directly isolated from cyh2S/cyh2S wine yeasts. Heterozygous cyh2R/cyh2S hybrid clones vary in genetic instability as measured by loss of heterozygosity at cyh2. There were two main classes of hybrids. The lawn hybrids have high genetic instability and generally become cyh2R/cyh2R homozygotes and lose the killer phenotype under nonselective conditions. The papilla hybrids have a much lower rate of loss of heterozygosity and maintain the killer phenotype. The genetic instability in lawn hybrids is 3 to 5 orders of magnitude greater than the highest loss-of-heterozygosity rates previously reported. Molecular mechanisms such as DNA repair by break-induced replication might account for the asymmetrical loss of heterozygosity. This loss-of-heterozygosity phenomenon could be economically important if it causes sudden phenotype changes in industrial or pathogenic yeasts and of more basic importance to the degree that it influences the evolution of naturally occurring yeast populations. PMID:15294803

  9. Development of Hybrid Product Breakdown Structure for NASA Ground Systems

    Science.gov (United States)

    Monaghan, Mark W.; Henry, Robert J.

    2013-01-01

    The Product Breakdown Structure is traditionally a method of identification of the products of a project in a tree structure. It is a tool used to assess, plan, document, and display the equipment requirements for a project. It is part of a product based planning technique, and attempts to break down all components of a project in as much detail as possible, so that nothing is overlooked. The PBS for ground systems at the Kennedy Space Center is being developed to encompass the traditional requirements including the alignment of facility, systems, and components to the organizational hierarchy. The Ground Operations Product Breakdown Structure is a hybrid in nature in that some aspects of a work breakdown structure will be incorporated and merged with the Architecture Concept of Operations, Master Subsystem List, customer interface, and assigned management responsibility. The Ground Operations Product Breakdown Structure needs to be able to identify the flexibility of support differing customers (internal and external) usage of ground support equipment within the Kennedy Space Center launch and processing complex. The development of the Product Breakdown Structure is an iterative activity Initially documenting the organization hierarchy structure and relationships. The Product Breakdown Structure identifies the linkage between the customer program requirements, allocation of system resources, development of design goals, and identification logistics products. As the Product Breakdown Structure progresses the incorporation of the results of requirement planning for the customer occurs identifying facility needs and systems. The mature Product Breakdown Structure is baselined with a hierarchical drawing, the Product Breakdown Structure database, and an associated document identifying the verification of the data through the life cycle of the program/product line. This paper will document, demonstrate, and identify key aspects of the life cycle of a Hybrid Product

  10. Technology for Hybrid Pepper Seed Production in China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    History of hybrid pepper seed production, the status of annually balanced production, and innovative techniques for the large-scale seed production in China are reviewed. Helped by the technological breakthroughs in these fields, China has been the largest base for hybrid pepper seed production in the world.

  11. Hybrid protocols plus natural treatments for inflammatory conditions.

    Science.gov (United States)

    1998-01-01

    Hybrid protocols combine one, two, or three pharmaceutical drugs with several nutritional or immune-based therapies. These protocols are not limited solely to FDA-approved drugs or strictly to alternative therapies. The rationale for using a hybrid protocol is to find an effective antiviral regimen that also restores immune function. The goal is to obtain the benefits of protease inhibitors without viral resistance and side effects which include problems with fat metabolism and cholesterol levels. Natural treatments for inflammatory conditions are also described. Options include licorice root, ginger root, and slippery elm.

  12. Synthetic glycosylated natural products have satisfactory activities.

    Science.gov (United States)

    Huang, Gangliang; Mei, Xinya

    2014-01-01

    Many natural products contain sugar residues, which are essential components for great medicinal importance. The sugar moieties can improve water-solubility of natural products and decrease their toxicity. At the same time, the glycosidic residues are crucial for the activities of natural products. Much effort has been expended over the past decades in developing novel and efficient methodologies to synthesize the glycosylated natural products. This review highlights recent developments in the synthesis of glycosylated natural products. The structure-activity relationships of some of these glycosylated natural products, together with the structure characteristics of their interaction with the biological targets, are also involved.

  13. Natural and engineered biosynthesis of fluorinated natural products.

    Science.gov (United States)

    Walker, Mark C; Chang, Michelle C Y

    2014-09-21

    Both natural products and synthetic organofluorines play important roles in the discovery and design of pharmaceuticals. The combination of these two classes of molecules has the potential to be useful in the ongoing search for new bioactive compounds but our ability to produce site-selectively fluorinated natural products remains limited by challenges in compatibility between their high structural complexity and current methods for fluorination. Living systems provide an alternative route to chemical fluorination and could enable the production of organofluorine natural products through synthetic biology approaches. While the identification of biogenic organofluorines has been limited, the study of the native organisms and enzymes that utilize these compounds can help to guide efforts to engineer the incorporation of this unusual element into complex pharmacologically active natural products. This review covers recent advances in understanding both natural and engineered production of organofluorine natural products.

  14. Hot springs and cool natural products.

    Science.gov (United States)

    Kwon, Ho Jeong; Lee, Choong Hwan; Osada, Hiroyuki; Yoshida, Minoru; Imoto, Masaya

    2008-08-01

    Natural products have played a unique role in providing new tools and insights in chemical biology. The tremendous value of natural products was highlighted by scientists from Korea and Japan at the 4(th) Korea-Japan Chemical Biology symposium.

  15. Nigerian Journal of Natural Products and Medicine

    African Journals Online (AJOL)

    Nigerian Journal of Natural Products and Medicine. ... 1982 dedicated to the promotion of Pharmacognosy, Natural Products and Traditional Medicine. .... Acuminatoside: a new anticancer compound from the maiden breast plant · EMAIL FULL ...

  16. Teaching 'natural product chemistry' in Tanzania | Buchanan ...

    African Journals Online (AJOL)

    Teaching 'natural product chemistry' in Tanzania. ... PROMOTING ACCESS TO AFRICAN RESEARCH. AFRICAN JOURNALS ONLINE (AJOL) · Journals ... Natural products 'historically' and 'today' have vast importance. This article describes ...

  17. Hybrid-Electric Vehicle with Natural Gas-Diesel Engine

    Directory of Open Access Journals (Sweden)

    Lino Guzzella

    2013-07-01

    Full Text Available In this paper we demonstrate the potential of combining electric hybridization with a dual-fuel natural gas-Diesel engine. We show that carbon dioxide emissions can be reduced to 43 gram per kilometer with a subcompact car on the New European Driving Cycle (NEDC. The vehicle is operated in charge-sustaining mode, which means that all energy is provided by the fuel. The result is obtained by hardware-in-the-loop experiments where the engine is operated on a test bench while the rest of the powertrain as well as the vehicle are simulated. By static engine measurements we demonstrate that the natural gas-Diesel engine reaches efficiencies of up to 39.5%. The engine is operated lean at low loads with low engine out nitrogen oxide emissions such that no nitrogen oxide aftertreatment is necessary. At medium to high loads the engine is operated stoichiometrically, which enables the use of a cost-efficient three-way catalytic converter. By vehicle emulation of a non-hybrid vehicle on the Worldwide harmonized Light vehicles Test Procedure (WLTP, we demonstrate that transient operation of the natural gas-Diesel engine is also possible, thus enabling a non-hybridized powertrain as well.

  18. Misassigned natural products and their revised structures.

    Science.gov (United States)

    Yoo, Hye-Dong; Nam, Sang-Jip; Chin, Young-Won; Kim, Min-Sun

    2016-02-01

    Natural products are a major pipeline for drug development and are responsible for more than 50 % of drugs on the market. NMR is a fundamental and powerful tool for the structure determination of natural products. It is essential to provide unambiguous chemical structure information on natural products in drug development research, including the structure-activity relationship, derivatization and pharmacokinetic/pharmacodynamic studies. Advancement of NMR instruments has made it possible to deal with nanomole-scale natural products for structure elucidation, but misinterpretation of NMR spectra still occurs. We review 21 natural products with revised chemical structures and the methods used for those revisions.

  19. Molecular identification of intergenus crosses involving catfish hybrids: risks for aquaculture production

    Directory of Open Access Journals (Sweden)

    Diogo T. Hashimoto

    Full Text Available ABSTRACT Monitoring of the interspecific hybrid production and trade is essential for the appropriate management of these animals in fish farms. The identification of catfish hybrids by morphological analysis is unreliable, particularly of juveniles and post-F1 individuals. Therefore, in the present study, we used five molecular markers (four nuclear genes and one mitochondrial gene to detect hybrids in the trade of pimelodid juvenile fish from different stocks purchased of five seed producers in Brazil. Samples commercialized as pintado (pure species Pseudoplatystoma corruscans from three fish farms were genetically identified as hybrid cachapinta (♀ P. reticulatum x ♂ P. corruscans . In the stocks purchased as cachandiá (hybrid between ♀ P. reticulatum x ♂ Leiarius marmoratus and cachapira (hybrid between ♀ P. reticulatum x ♂ Phractocephalus hemioliopterus , we suggested the occurrence of intergenus crosses involving the hybrid cachapinta, which was used instead of the pure species P. reticulatum . The problems involving the hybrid cachapinta production were discussed in the present study, especially because these animals have caused genetic contamination and threatened the genetic integrity of natural and cultivated populations. In order to improve the surveillance of the production and provide criteria for the correct management of catfish hybrids, genetic markers has become an excellent alternative to the morphological identification, including juveniles or post-F1 generations.

  20. Nature-inspired design of hybrid intelligent systems

    CERN Document Server

    Castillo, Oscar; Kacprzyk, Janusz

    2017-01-01

    This book highlights recent advances in the design of hybrid intelligent systems based on nature-inspired optimization and their application in areas such as intelligent control and robotics, pattern recognition, time series prediction, and optimization of complex problems. The book is divided into seven main parts, the first of which addresses theoretical aspects of and new concepts and algorithms based on type-2 and intuitionistic fuzzy logic systems. The second part focuses on neural network theory, and explores the applications of neural networks in diverse areas, such as time series prediction and pattern recognition. The book’s third part presents enhancements to meta-heuristics based on fuzzy logic techniques and describes new nature-inspired optimization algorithms that employ fuzzy dynamic adaptation of parameters, while the fourth part presents diverse applications of nature-inspired optimization algorithms. In turn, the fifth part investigates applications of fuzzy logic in diverse areas, such as...

  1. Biosynthesis of natural products containing β-amino acids.

    Science.gov (United States)

    Kudo, Fumitaka; Miyanaga, Akimasa; Eguchi, Tadashi

    2014-08-01

    Covering: up to January, 2014. We focus here on β-amino acids as components of complex natural products because the presence of β-amino acids produces structural diversity in natural products and provides characteristic architectures beyond those of ordinary α-L-amino acids, thus generating significant and unique biological functions in nature. In this review, we first survey the known bioactive β-amino acid-containing natural products including nonribosomal peptides, macrolactam polyketides, and nucleoside-β-amino acid hybrids. Next, the biosynthetic enzymes that form β-amino acids from α-amino acids and the de novo synthesis of β-amino acids are summarized. Then, the mechanisms of β-amino acid incorporation into natural products are reviewed. Because it is anticipated that the rational swapping of the β-amino acid moieties with various side chains and stereochemistries by biosynthetic engineering should lead to the creation of novel architectures and bioactive compounds, the accumulation of knowledge regarding β-amino acid-containing natural product biosynthetic machinery could have a significant impact in this field. In addition, genome mining of characteristic β-amino acid biosynthetic genes and unique β-amino acid incorporation machinery could lead to the discovery of new β-amino acid-containing natural products.

  2. Evading the Lyth bound in hybrid natural inflation

    Energy Technology Data Exchange (ETDEWEB)

    Hebecker, A.; Kraus, S.C. [Heidelberg Univ. (Germany). Inst. fuer Theoretische Physik; Westphal, Alexander [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany). Theory Group

    2013-05-15

    Generically, the gravitational-wave or tensor-mode contribution to the primordial curvature spectrum of inflation is tiny if the field-range of the inflaton is much smaller than the Planck scale. We show that this pessimistic conclusion is naturally avoided in a rather broad class of small-field models. More specifically, we consider models where an axion-like shift symmetry keeps the inflaton potential flat (up to non-perturbative cosine-shaped modulations), but inflation nevertheless ends in a waterfall-regime, as is typical for hybrid inflation. In such hybrid natural inflation scenarios (examples are provided by Wilson line inflation and fluxbrane inflation), the slow-roll parameter {epsilon} can be sizable during an early period (relevant for the CMB spectrum). Subsequently, {epsilon} quickly becomes very small before the tachyonic instability eventually terminates the slow-roll regime. In this scenario, one naturally generates a considerable tensor-mode contribution in the curvature spectrum, collecting nevertheless the required amount of e-foldings during the final period of inflation. While non-observation of tensors by Planck is certainly not a problem, a discovery in the medium to long term future is realistic.

  3. HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING

    Energy Technology Data Exchange (ETDEWEB)

    Girish Srinivas; Steven C. Gebhard; David W. DeBerry

    2001-05-01

    This first quarter report of 2001 describes progress on a project funded by the U.S. Department of Energy (DOE) to test a hybrid sulfur recovery process for natural gas upgrading. The process concept represents a low cost option for direct treatment of natural gas streams to remove H{sub 2}S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day. This process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both on-shore and offshore applications. CrystaSulf{trademark} (service mark of Gas Research Institute) is a new nonaqueous sulfur recovery process that removes hydrogen sulfide (H{sub 2}S) from gas streams and converts it into elemental sulfur. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, approximately 1/3 of the total H{sub 2}S in the natural gas is first oxidized to SO{sub 2} at low temperatures over a heterogeneous catalyst. Low temperature oxidation is done so that the H{sub 2}S can be oxidized in the presence of methane and other hydrocarbons without oxidation of the hydrocarbons. The project involves the development of a catalyst using laboratory/bench-scale catalyst testing, and then demonstration of the catalyst at CrystaTech's pilot plant in west Texas. During this reporting periods new catalyst formulations were tested. The experiments showed that the newest catalyst has slightly better performance, but catalyst TDA No.2 is still superior overall for use with the hybrid CrystaSulf process due to lower costs. Plans for catalyst pelletization and continued testing are described.

  4. Natural products and body weight control

    Directory of Open Access Journals (Sweden)

    Jay Lee

    2011-01-01

    Full Text Available The purpose of the review was to summarise the effect of some commonly available natural products used for body weight management. We collected data from PubMed and scientific journals. There are numerous publications on this topic, however we have summarized the most commonly available and potent natural products from recent 53 publications. The natural products analyzed in this paper include catechins, capsaicin, conjugated linoleic acid, fucoxanthin, soy isoflavone, glabridin, astaxanthin and cyaniding-3-glucoside. These natural products are effective and safe for body weight management. Further studies need to be conducted to investigate the mechanism of action, metabolism, long term safety and side effects of these natural products, as well as interactions between these natural products with dietary components.

  5. Accounting Of Products Collected From Nature

    Directory of Open Access Journals (Sweden)

    Ahmet Gökgöz

    2015-12-01

    Full Text Available Products from nature can be classified as “production” or “collection from nature” within agricultural production. Products collected from nature vary in type and can sum up to important quantities. Thyme, mushroom, chestnut, sage, linden, saffron from plant origin can be given as examples to products from nature as well as fish, mussel, octopus, birds from animal origin. This study covers the accounting area of products obtained from nature. The evaluation of collection of these products from nature in terms of agricultural operation poses great importance for accounting issues. Thus, special care will be given to issues of accounting of these products within the scope of Turkish Tax Legislation and Turkish Accounting Standards

  6. Super Natural II--a database of natural products.

    Science.gov (United States)

    Banerjee, Priyanka; Erehman, Jevgeni; Gohlke, Björn-Oliver; Wilhelm, Thomas; Preissner, Robert; Dunkel, Mathias

    2015-01-01

    Natural products play a significant role in drug discovery and development. Many topological pharmacophore patterns are common between natural products and commercial drugs. A better understanding of the specific physicochemical and structural features of natural products is important for corresponding drug development. Several encyclopedias of natural compounds have been composed, but the information remains scattered or not freely available. The first version of the Supernatural database containing ∼ 50,000 compounds was published in 2006 to face these challenges. Here we present a new, updated and expanded version of natural product database, Super Natural II (http://bioinformatics.charite.de/supernatural), comprising ∼ 326,000 molecules. It provides all corresponding 2D structures, the most important structural and physicochemical properties, the predicted toxicity class for ∼ 170,000 compounds and the vendor information for the vast majority of compounds. The new version allows a template-based search for similar compounds as well as a search for compound names, vendors, specific physical properties or any substructures. Super Natural II also provides information about the pathways associated with synthesis and degradation of the natural products, as well as their mechanism of action with respect to structurally similar drugs and their target proteins.

  7. Counting on natural products for drug design

    Science.gov (United States)

    Rodrigues, Tiago; Reker, Daniel; Schneider, Petra; Schneider, Gisbert

    2016-06-01

    Natural products and their molecular frameworks have a long tradition as valuable starting points for medicinal chemistry and drug discovery. Recently, there has been a revitalization of interest in the inclusion of these chemotypes in compound collections for screening and achieving selective target modulation. Here we discuss natural-product-inspired drug discovery with a focus on recent advances in the design of synthetically tractable small molecules that mimic nature's chemistry. We highlight the potential of innovative computational tools in processing structurally complex natural products to predict their macromolecular targets and attempt to forecast the role that natural-product-derived fragments and fragment-like natural products will play in next-generation drug discovery.

  8. Natural Cinnamic Acids, Synthetic Derivatives and Hybrids with Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Juan David Guzman

    2014-11-01

    Full Text Available Antimicrobial natural preparations involving cinnamon, storax and propolis have been long used topically for treating infections. Cinnamic acids and related molecules are partly responsible for the therapeutic effects observed in these preparations. Most of the cinnamic acids, their esters, amides, aldehydes and alcohols, show significant growth inhibition against one or several bacterial and fungal species. Of particular interest is the potent antitubercular activity observed for some of these cinnamic derivatives, which may be amenable as future drugs for treating tuberculosis. This review intends to summarize the literature data on the antimicrobial activity of the natural cinnamic acids and related derivatives. In addition, selected hybrids between cinnamic acids and biologically active scaffolds with antimicrobial activity were also included. A comprehensive literature search was performed collating the minimum inhibitory concentration (MIC of each cinnamic acid or derivative against the reported microorganisms. The MIC data allows the relative comparison between series of molecules and the derivation of structure-activity relationships.

  9. Analysis on Dry Matter Production Characteristics of Super Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Six middle-season indica hybrid rice combinations,including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha,were used as materials to study the dry matter production characteristics.The super hybrid rice showed a high ability in dry matter production and accumulation and its yield enhanced with the increase of dry matter accumulation.The advantage period of dry matter production in the super hybrid rice was mainly at the middle and late growth stages compared with the check.The grain yield had no significant correlation with the dry matter accumulation before the elongation stage while had a significantly positive correlation with the dry matter accumulation from the elongation to maturity stages in super hybrid rice.There were more dry matter in vegetative organs at the heading stage in the super hybrid rice but its contribution to yield (apparent conversion percentage) was averagely 4.3 percent points lower than that in the check.For crop growth rate (CGR),the comparative advantage of super hybrid rice was at the middle and late stages,especially after flowering.Moreover,as the rising of leaf area index (LAI) and leaf area duration (LAD),CGR enhanced.The total LAD and the mean of LAD per day of super hybrid rice was about 14.79% and 10.31% higher than those of the check,respectively.The results indicate that the high yield of super hybrid rice mostly comes from the products of photosynthesis after heading,which is shown by the increased CGR at middle and later stages.It is suggested that LAD character might be used to better explain the advantage in the dry matter production of super hybrid rice than LAI.

  10. Natural Connections on Riemannian Product Manifolds

    OpenAIRE

    Gribacheva, Dobrinka

    2011-01-01

    A Riemannian almost product manifold with integrable almost product structure is called a Riemannian product manifold. In the present paper the natural connections on such manifolds are studied, i.e. the linear connections preserving the almost product structure and the Riemannian metric.

  11. Food production and nature conservation

    NARCIS (Netherlands)

    Gordon, Iain J.; Squire, Geoff R.; Prins, Herbert H.T.

    2016-01-01

    Feeding the world's growing human population is increasingly challenging, especially as more people adopt a western diet and lifestyle. Doing so without causing damage to nature poses an even greater challenge. This book argues that in order to create a sustainable food supply whilst conserving

  12. Functional chromatographic technique for natural product isolation†

    Science.gov (United States)

    Lau, Eric C.; Mason, Damian J.; Eichhorst, Nicole; Engelder, Pearce; Mesa, Celestina; Kithsiri Wijeratne, E. M.; Gunaherath, G. M. Kamal B.; Leslie Gunatilaka, A. A.

    2015-01-01

    Natural product discovery arises through a unique interplay between chromatographic purification and biological assays. Currently, most techniques used for natural product purification deliver leads without a defined biological action. We now describe a technique, referred to herein as functional chromatography, that deploys biological affinity as the matrix for compound isolation. PMID:25588099

  13. Functional chromatographic technique for natural product isolation†

    OpenAIRE

    Lau, Eric C.; Mason, Damian J.; Eichhorst, Nicole; Engelder, Pearce; Mesa, Celestina; Kithsiri Wijeratne, E. M.; Gunaherath, G. M. Kamal B.; Leslie Gunatilaka, A. A.; La Clair, James J.; Chapman, Eli

    2015-01-01

    Natural product discovery arises through a unique interplay between chromatographic purification and biological assays. Currently, most techniques used for natural product purification deliver leads without a defined biological action. We now describe a technique, referred to herein as functional chromatography, that deploys biological affinity as the matrix for compound isolation.

  14. Bioactive natural products from novel microbial sources.

    Science.gov (United States)

    Challinor, Victoria L; Bode, Helge B

    2015-09-01

    Despite the importance of microbial natural products for human health, only a few bacterial genera have been mined for the new natural products needed to overcome the urgent threat of antibiotic resistance. This is surprising, given that genome sequencing projects have revealed that the capability to produce natural products is not a rare feature among bacteria. Even the bacteria occurring in the human microbiome produce potent antibiotics, and thus potentially are an untapped resource for novel compounds, potentially with new activities. This review highlights examples of bacteria that should be considered new sources of natural products, including anaerobes, pathogens, and symbionts of humans, insects, and nematodes. Exploitation of these producer strains, combined with advances in modern natural product research methodology, has the potential to open the way for a new golden age of microbial therapeutics.

  15. A Hybrid Fuzzy Model for Lean Product Development Performance Measurement

    Science.gov (United States)

    Osezua Aikhuele, Daniel; Mohd Turan, Faiz

    2016-02-01

    In the effort for manufacturing companies to meet up with the emerging consumer demands for mass customized products, many are turning to the application of lean in their product development process, and this is gradually moving from being a competitive advantage to a necessity. However, due to lack of clear understanding of the lean performance measurements, many of these companies are unable to implement and fully integrated the lean principle into their product development process. Extensive literature shows that only few studies have focus systematically on the lean product development performance (LPDP) evaluation. In order to fill this gap, the study therefore proposed a novel hybrid model based on Fuzzy Reasoning Approach (FRA), and the extension of Fuzzy-AHP and Fuzzy-TOPSIS methods for the assessment of the LPDP. Unlike the existing methods, the model considers the importance weight of each of the decision makers (Experts) since the performance criteria/attributes are required to be rated, and these experts have different level of expertise. The rating is done using a new fuzzy Likert rating scale (membership-scale) which is designed such that it can address problems resulting from information lost/distortion due to closed-form scaling and the ordinal nature of the existing Likert scale.

  16. Natural language parsing in a hybrid connectionist-symbolic architecture

    Science.gov (United States)

    Mueller, Adrian; Zell, Andreas

    1991-03-01

    Most connectionist parsers either cannot guarantee the correctness of their derivations or have to simulate a serial flow of control. In the first case, users have to restrict the tasks (e.g. parse less complex or shorter sentences) of the parser or they need to believe in the soundness of the result. In the second case, the resulting network has lost most of its attractivity because seriality needs to be hard-coded into the structure of the net. We here present a hybrid symbolic connectionist parser, which was designed to fulfill the following goals: (1) parsing of sentences without length restriction, (2) soundness and completeness for any context-free grammar, and (3) learning the applicability of parsing rules with a neural network. Our hybrid architecture consists of a serial parsing algorithm and a trainable net. BrainC (Backtracking and Backpropagation in C) combines the well known shift-reduce parsing technique with backtracking with a backpropagation network to learn and represent the typical properties of the trained natural language grammars. The system has been implemented as a subsystem of the Rochester Connectionist Simulator (RCS) on SUN- Workstations and was tested with several grammars for English and German. We discuss how BrainC reached its design goals and what results we observed.

  17. Targeting Nuclear Receptors with Marine Natural Products

    Directory of Open Access Journals (Sweden)

    Chunyan Yang

    2014-01-01

    Full Text Available Nuclear receptors (NRs are important pharmaceutical targets because they are key regulators of many metabolic and inflammatory diseases, including diabetes, dyslipidemia, cirrhosis, and fibrosis. As ligands play a pivotal role in modulating nuclear receptor activity, the discovery of novel ligands for nuclear receptors represents an interesting and promising therapeutic approach. The search for novel NR agonists and antagonists with enhanced selectivities prompted the exploration of the extraordinary chemical diversity associated with natural products. Recent studies involving nuclear receptors have disclosed a number of natural products as nuclear receptor ligands, serving to re-emphasize the translational possibilities of natural products in drug discovery. In this review, the natural ligands of nuclear receptors will be described with an emphasis on their mechanisms of action and their therapeutic potentials, as well as on strategies to determine potential marine natural products as nuclear receptor modulators.

  18. Natural food pigments application in food products

    Directory of Open Access Journals (Sweden)

    Emilia Janiszewska-Turak

    2016-12-01

    Full Text Available Natural pigments, food compounds, are responsible for the colour of the products. These additives can impart, to deepen or renew the colour of the product, if it has been lost while processing. They also improve the taste of the product and facilitate its identification. It is hard to imagine today’s food industry without the use of pigments. Presently, more and more conscious con­sumers are demanding products to be coloured with natural pigments or any pigment added to the final product. Artificial pigments are considered to be harmful and undesirable so food manufacturers focus on the use of natural colour substances. 16 natural pigments are presently permitted to be used. These compounds are: betalains – betanin, quinones – cochineal, flavonoids – anthocyan­ins, isoprenoids – carotene, annatto (bixin, norbixin, paprika extract, lutein, canthaxanthin, porphyrins – chlorophylls and chlorophyllins and copper complexes of these compounds, and others: caramels, curcumin, or plant coal.

  19. Breeding Strategy of Acacia Hybrid (Acacia mangium × A. auriculiformis to Increase Forest Plantation Productivity in Indonesia

    Directory of Open Access Journals (Sweden)

    Sri Sunarti

    2013-08-01

    Full Text Available Acacia hybrid (Acacia mangium× A.auriculiformis shows better growth and wood properties, and tolerance to pest and disease. Currently, acacia hybrid breeding strategy was developed through naturally hybrid selected from trees grown in plantation. However, mass propagation of acacia hybrid using such kind of strategy was not satisfied due to ageing effect. This study was aimed to develop a new acacia hybrid breeding strategy using controlled pollination hybridization technique. The strategy was developed through a series of research: flowering, crossing, hybrid identification, clone multiplication, and clonal test. The results of study showed that the series of research for developing acacia hybrid breeding strategy was achieved. Flowering time synchronization provided a high probability for the success of controlled pollination hybridization. Leaves taxonomy at seedling stage revealed to be an efective way to identify acacia hybrid with acuracy of 92.2%. The acacia hybrid was succesfully propagated using shoot cutting at rate of 78.1%. The best selected clones of acacia hybrid outperformed in height growth at rates of 17.28% over to superior pure parents, which is equivalent to the estimated stand productivity at around 48 m3 ha-1 y-1. The series of research provided a new effective and efficient breeding strategy for acacia hybrid.Keywords: Acacia auriculiformis,  Acacia mangium, acacia hybrid, controlled pollination, breeding strategyDOI: 10.7226/jtfm.19.2.128

  20. New Synthetic Methods for Hypericum Natural Products

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Insik [Iowa State Univ., Ames, IA (United States)

    2006-01-01

    Organic chemistry has served as a solid foundation for interdisciplinary research areas, such as molecular biology and medicinal chemistry. An understanding of the biological activities and structural elucidations of natural products can lead to the development of clinically valuable therapeutic options. The advancements of modern synthetic methodologies allow for more elaborate and concise natural product syntheses. The theme of this study centers on the synthesis of natural products with particularly challenging structures and interesting biological activities. The synthetic expertise developed here will be applicable to analog syntheses and to other research problems.

  1. Cancer wars: natural products strike back

    Science.gov (United States)

    Basmadjian, Christine; Zhao, Qian; Bentouhami, Embarek; Djehal, Amel; Nebigil, Canan G.; Johnson, Roger A.; Serova, Maria; de Gramont, Armand; Faivre, Sandrine; Raymond, Eric; Désaubry, Laurent G.

    2014-01-01

    Natural products have historically been a mainstay source of anticancer drugs, but in the 90's they fell out of favor in pharmaceutical companies with the emergence of targeted therapies, which rely on antibodies or small synthetic molecules identified by high throughput screening. Although targeted therapies greatly improved the treatment of a few cancers, the benefit has remained disappointing for many solid tumors, which revitalized the interest in natural products. With the approval of rapamycin in 2007, 12 novel natural product derivatives have been brought to market. The present review describes the discovery and development of these new anticancer drugs and highlights the peculiarities of natural product and new trends in this exciting field of drug discovery. PMID:24822174

  2. Sources for Leads: Natural Products and Libraries.

    Science.gov (United States)

    van Herwerden, Eric F; Süssmuth, Roderich D

    2016-01-01

    Natural products have traditionally been a major source of leads in the drug discovery process. However, the development of high-throughput screening led to an increased interest in synthetic methods that enabled the rapid construction of large libraries of molecules. This resulted in the termination or downscaling of many natural product research programs, but the chemical libraries did not necessarily produce a larger amount of drug leads. On one hand, this chapter explores the current state of natural product research within the drug discovery process. On the other hand it evaluates the efforts made to increase the amount of leads generated from chemical libraries and considers what role natural products could play here.

  3. Cancer wars: Natural products strike back

    Science.gov (United States)

    Basmadjian, Christine; Zhao, Qian; Djehal, Amel; Bentouhami, Embarek; Nebigil, Canan; Johnson, Roger; Serova, Maria; De Gramont, Armand; Faivre, Sandrine; Raymond, Eric; Désaubry, Laurent

    2014-05-01

    Natural products have historically been a mainstay source of anticancer drugs, but in the 90’s they fell out of favor in pharmaceutical companies with the emergence of targeted therapies, which rely on antibodies or small synthetic molecules identified by high throughput screening. Although targeted therapies greatly improved the treatment of a few cancers, the benefit has remained disappointing for many sol¬¬id tumors, which revitalized the interest in natural products. With the approval of rapamycin in 2007, twelve novel natural product derivatives have been brought to market. The present review describes the discovery and development of these new anticancer drugs and highlights the peculiarities of natural product and new trends in this exciting field of drug discovery.

  4. ARTEMISININ: THE JOURNEY FROM NATURAL PRODUCT TO ...

    African Journals Online (AJOL)

    services, many parents lose their children to complications ... ARTEMISININ: THE JOURNEY FROM NATURAL PRODUCT TO NOBEL PRIZE. SUMMARY ... Medicine, where she has remained for over 55 years. After joining ... An advantage of.

  5. High impact technologies for natural products screening.

    Science.gov (United States)

    Koehn, Frank E

    2008-01-01

    Natural products have historically been a rich source of lead molecules in drug discovery. However, natural products have been de-emphasized as high throughput screening resources in the recent past, in part because of difficulties in obtaining high quality natural products screening libraries, or in applying modern screening assays to these libraries. In addition, natural products programs based on screening of extract libraries, bioassay-guided isolation, structure elucidation and subsequent production scale-up are challenged to meet the rapid cycle times that are characteristic of the modern HTS approach. Fortunately, new technologies in mass spectrometry, NMR and other spectroscopic techniques can greatly facilitate the first components of the process - namely the efficient creation of high-quality natural products libraries, bimolecular target or cell-based screening, and early hit characterization. The success of any high throughput screening campaign is dependent on the quality of the chemical library. The construction and maintenance of a high quality natural products library, whether based on microbial, plant, marine or other sources is a costly endeavor. The library itself may be composed of samples that are themselves mixtures - such as crude extracts, semi-pure mixtures or single purified natural products. Each of these library designs carries with it distinctive advantages and disadvantages. Crude extract libraries have lower resource requirements for sample preparation, but high requirements for identification of the bioactive constituents. Pre-fractionated libraries can be an effective strategy to alleviate interferences encountered with crude libraries, and may shorten the time needed to identify the active principle. Purified natural product libraries require substantial resources for preparation, but offer the advantage that the hit detection process is reduced to that of synthetic single component libraries. Whether the natural products library

  6. Cancer wars: Natural products strike back

    OpenAIRE

    Christine eBasmadjian; Qian eZhao; Amel eDjehal; Embarek eBentouhami; Nebigil, Canan G.; Johnson, Roger A.; Maria eSerova; Armand eDe Gramont; Sandrine eFaivre; Eric eRaymond; Désaubry, Laurent G.

    2014-01-01

    Natural products have historically been a mainstay source of anticancer drugs, but in the 90’s they fell out of favor in pharmaceutical companies with the emergence of targeted therapies, which rely on antibodies or small synthetic molecules identified by high throughput screening. Although targeted therapies greatly improved the treatment of a few cancers, the benefit has remained disappointing for many sol¬¬id tumors, which revitalized the interest in natural products. With the approval of ...

  7. Cancer wars: natural products strike back

    OpenAIRE

    Basmadjian, Christine; Zhao, Qian; Bentouhami, Embarek; Djehal, Amel; Nebigil, Canan G.; Johnson, Roger A.; Serova, Maria; Gramont, Armand de; Faivre, Sandrine; Raymond, Eric; Désaubry, Laurent G.

    2014-01-01

    Natural products have historically been a mainstay source of anticancer drugs, but in the 90's they fell out of favor in pharmaceutical companies with the emergence of targeted therapies, which rely on antibodies or small synthetic molecules identified by high throughput screening. Although targeted therapies greatly improved the treatment of a few cancers, the benefit has remained disappointing for many solid tumors, which revitalized the interest in natural products. With the approval of ra...

  8. Reconstructing fungal natural product biosynthetic pathways.

    Science.gov (United States)

    Lazarus, C M; Williams, K; Bailey, A M

    2014-10-01

    Large scale fungal genome sequencing has revealed a multitude of potential natural product biosynthetic pathways that remain uncharted. Here we describe some of the methods that have been used to explore them via heterologous gene expression. We focus on filamentous fungal hosts and discuss the technological challenges and successes behind the reconstruction of fungal natural product pathways. Optimised, efficient heterologous expression of reconstructed biosynthetic pathways promises progress in the discovery of novel compounds that could be utilised by the pharmaceutical and agrochemical industries.

  9. HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING

    Energy Technology Data Exchange (ETDEWEB)

    Girish Srinivas; Steven C. Gebhard; David W. DeBerry

    2002-04-01

    This first quarter report of 2002 describes progress on a project funded by the U.S. Department of Energy (DOE) to test a hybrid sulfur recovery process for natural gas upgrading. The process concept represents a low cost option for direct treatment of natural gas streams to remove H{sub 2}S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day. This process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both on-shore and offshore applications. CrystaSulf{sup SM} (service mark of CrystaTech, Inc.) is a new nonaqueous sulfur recovery process that removes hydrogen sulfide (H{sub 2}S) from gas streams and converts it into elemental sulfur. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, approximately 1/3 of the total H{sub 2}S in the natural gas is first oxidized to SO{sub 2} at low temperatures over a heterogeneous catalyst. Low temperature oxidation is done so that the H{sub 2}S can be oxidized in the presence of methane and other hydrocarbons without oxidation of the hydrocarbons. The project involves the development of a catalyst using laboratory/bench-scale catalyst testing, and then demonstration of the catalyst at CrystaTech's pilot plant in west Texas. In a previous reporting period tests were done to determine the effect of hydrocarbons such as n-hexane on catalyst performance with and without H{sub 2}S present. The experiments showed that hexane oxidation is suppressed when H{sub 2}S is present. Hexane represents the most reactive of the C1 to C6 series of alkanes. Since hexane exhibits low reactivity under H{sub 2}S oxidation conditions, and more importantly, does not

  10. HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING

    Energy Technology Data Exchange (ETDEWEB)

    Girish Srinivas; Steven C. Gebhard; David W. DeBerry

    2002-07-01

    This second quarter report of 2002 describes progress on a project funded by the U.S. Department of Energy (DOE) to test a hybrid sulfur recovery process for natural gas upgrading. The process concept represents a low cost option for direct treatment of natural gas streams to remove H{sub 2}S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day. This process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both on-shore and offshore applications. CrystaSulf (service mark of CrystaTech, Inc.) is a new nonaqueous sulfur recovery process that removes hydrogen sulfide (H{sub 2}S) from gas streams and converts it into elemental sulfur. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, approximately 1/3 of the total H{sub 2}S in the natural gas is first oxidized to SO{sub 2} at low temperatures over a heterogeneous catalyst. Low temperature oxidation is done so that the H{sub 2}S can be oxidized in the presence of methane and other hydrocarbons without oxidation of the hydrocarbons. The project involves the development of a catalyst using laboratory/bench-scale catalyst testing, and then demonstration of the catalyst at CrystaTech's pilot plant in west Texas. Previous reports described development of a catalyst with the required selectivity and efficiency for producing sulfur dioxide from H{sub 2}S. In the laboratory, the catalyst was shown to be robust and stable in the presence of several intentionally added contaminants, including condensate from the pilot plant site. This report describes testing using the laboratory apparatus but operated at the pilot plant using the actual pilot

  11. TEACHING 'NATURAL PRODUCT CHEMISTRY' IN TANZANIA

    African Journals Online (AJOL)

    Temechegn

    natural product chemistry or chemistry of natural medicines [4]. There is even ... The course is an optional course (not core) open to 3rd year (final year) students in the. Faculty of .... a gift to the newborn Jesus (Matthew 2:11) [24]. • Olive oil is ...

  12. Hybrid Adsorptive and Oxidative Removal of Natural Organic Matter Using Iron Oxide-Coated Pumice Particles

    Directory of Open Access Journals (Sweden)

    Sehnaz Sule Kaplan Bekaroglu

    2016-01-01

    Full Text Available The aim of this work was to combine adsorptive and catalytic properties of iron oxide surfaces in a hybrid process using hydrogen peroxide and iron oxide-coated pumice particles to remove natural organic matter (NOM in water. Experiments were conducted in batch, completely mixed reactors using various original and coated pumice particles. The results showed that both adsorption and catalytic oxidation mechanisms played role in the removal of NOM. The hybrid process was found to be effective in removing NOM from water having a wide range of specific UV absorbance values. Iron oxide surfaces preferentially adsorbed UV280-absorbing NOM fractions. Furthermore, the strong oxidants produced from reactions among iron oxide surfaces and hydrogen peroxide also preferentially oxidized UV280-absorbing NOM fractions. Preloading of iron oxide surfaces with NOM slightly reduced the further NOM removal performance of the hybrid process. Overall, the results suggested that the tested hybrid process may be effective for removal of NOM and control disinfection by-product formation.

  13. Hybrid optimization model of product concepts

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Deficiencies of applying the simple genetic algorithm to generate concepts were specified. Based on analyzing conceptual design and the morphological matrix of an excavator, the hybrid optimization model of generating its concepts was proposed, viz. an improved adaptive genetic algorithm was applied to explore the excavator concepts in the searching space of conceptual design, and a neural network was used to evaluate the fitness of the population. The optimization of generating concepts was finished through the "evolution - evaluation" iteration. The results show that by using the hybrid optimization model, not only the fitness evaluation and constraint conditions are well processed, but also the search precision and convergence speed of the optimization process are greatly improved. An example is presented to demonstrate the advantages of the proposed method and associated algorithms.

  14. Assortative mating and the maintenance of population structure in a natural hybrid zone.

    Science.gov (United States)

    Culumber, Zachary W; Ochoa, Olivia M; Rosenthal, Gil G

    2014-08-01

    Understanding the factors that give rise to natural hybrid zones and govern their dynamics and structure is important to predicting the evolutionary consequences of hybridization. Here we use a combination of multigenerational population genetic data, mating patterns from a natural population, behavioral assays, and mark-recapture data within clinal hybrid zones of the genus Xiphophorus to test the role of assortative mating in maintaining population structure and the potential for ongoing genetic exchange between heterospecifics. Our data demonstrate that population structure is temporally robust and driven largely by assortative mating stemming from precopulatory isolation between pure species. Furthermore, mark-recapture data revealed that rates of migration within the same stream reach are far below the level needed to support population structure. In contrast to many empirical studies of natural hybrid zones, there appeared to be no hybrid male dysfunction or discrimination against hybrid males by pure parental females, and hybrid females mated and associated with pure species and hybrid males at random. Despite strong isolation between pure parentals, hybrids therefore can act as a conduit for genetic exchange between heterospecifics, which has been shown to increase the tempo of evolutionary change. Additionally, our findings highlight the complexity of natural hybrid zone dynamics, demonstrating that sexual and ecological selection together can give rise to patterns that do not fit classical models of hybrid zone evolution.

  15. Hybrid breeding in wheat: technologies to improve hybrid wheat seed production.

    Science.gov (United States)

    Whitford, Ryan; Fleury, Delphine; Reif, Jochen C; Garcia, Melissa; Okada, Takashi; Korzun, Viktor; Langridge, Peter

    2013-12-01

    Global food security demands the development and delivery of new technologies to increase and secure cereal production on finite arable land without increasing water and fertilizer use. There are several options for boosting wheat yields, but most offer only small yield increases. Wheat is an inbred plant, and hybrids hold the potential to deliver a major lift in yield and will open a wide range of new breeding opportunities. A series of technological advances are needed as a base for hybrid wheat programmes. These start with major changes in floral development and architecture to separate the sexes and force outcrossing. Male sterility provides the best method to block self-fertilization, and modifying the flower structure will enhance pollen access. The recent explosion in genomic resources and technologies provides new opportunities to overcome these limitations. This review outlines the problems with existing hybrid wheat breeding systems and explores molecular-based technologies that could improve the hybrid production system to reduce hybrid seed production costs, a prerequisite for a commercial hybrid wheat system.

  16. Microbial production of natural raspbery ketone

    NARCIS (Netherlands)

    Beekwilder, M.J.; Meer, van der I.M.; Sibbesen, O.; Broekgaarden, M.; Qvist, I.; Mikkelsen, J.D.; Hall, R.D.

    2007-01-01

    Raspberry ketone is an important compound for the flavour industry. It is frequently used in products such as soft drinks, sweets, puddings and ice creams. The compound can be produced by organic synthesis. Demand for natural raspberry ketone is growing considerably. However, this product is

  17. Microbial production of natural raspbery ketone

    NARCIS (Netherlands)

    Beekwilder, M.J.; Meer, van der I.M.; Sibbesen, O.; Broekgaarden, M.; Qvist, I.; Mikkelsen, J.D.; Hall, R.D.

    2007-01-01

    Raspberry ketone is an important compound for the flavour industry. It is frequently used in products such as soft drinks, sweets, puddings and ice creams. The compound can be produced by organic synthesis. Demand for natural raspberry ketone is growing considerably. However, this product is extreme

  18. Method for production of sorghum hybrids with selected flowering times

    Science.gov (United States)

    Mullet, John E.; Rooney, William L.

    2016-08-30

    Methods and composition for the production of sorghum hybrids with selected and different flowering times are provided. In accordance with the invention, a substantially continual and high-yield harvest of sorghum is provided. Improved methods of seed production are also provided.

  19. Method for production of sorghum hybrids with selected flowering times

    Energy Technology Data Exchange (ETDEWEB)

    Mullet, John E.; Rooney, William L.

    2016-08-30

    Methods and composition for the production of sorghum hybrids with selected and different flowering times are provided. In accordance with the invention, a substantially continual and high-yield harvest of sorghum is provided. Improved methods of seed production are also provided.

  20. Natural product discovery: past, present, and future.

    Science.gov (United States)

    Katz, Leonard; Baltz, Richard H

    2016-03-01

    Microorganisms have provided abundant sources of natural products which have been developed as commercial products for human medicine, animal health, and plant crop protection. In the early years of natural product discovery from microorganisms (The Golden Age), new antibiotics were found with relative ease from low-throughput fermentation and whole cell screening methods. Later, molecular genetic and medicinal chemistry approaches were applied to modify and improve the activities of important chemical scaffolds, and more sophisticated screening methods were directed at target disease states. In the 1990s, the pharmaceutical industry moved to high-throughput screening of synthetic chemical libraries against many potential therapeutic targets, including new targets identified from the human genome sequencing project, largely to the exclusion of natural products, and discovery rates dropped dramatically. Nonetheless, natural products continued to provide key scaffolds for drug development. In the current millennium, it was discovered from genome sequencing that microbes with large genomes have the capacity to produce about ten times as many secondary metabolites as was previously recognized. Indeed, the most gifted actinomycetes have the capacity to produce around 30-50 secondary metabolites. With the precipitous drop in cost for genome sequencing, it is now feasible to sequence thousands of actinomycete genomes to identify the "biosynthetic dark matter" as sources for the discovery of new and novel secondary metabolites. Advances in bioinformatics, mass spectrometry, proteomics, transcriptomics, metabolomics and gene expression are driving the new field of microbial genome mining for applications in natural product discovery and development.

  1. Using Genomics for Natural Product Structure Elucidation.

    Science.gov (United States)

    Tietz, Jonathan I; Mitchell, Douglas A

    2016-01-01

    Natural products (NPs) are the most historically bountiful source of chemical matter for drug development-especially for anti-infectives. With insights gleaned from genome mining, interest in natural product discovery has been reinvigorated. An essential stage in NP discovery is structural elucidation, which sheds light not only on the chemical composition of a molecule but also its novelty, properties, and derivatization potential. The history of structure elucidation is replete with techniquebased revolutions: combustion analysis, crystallography, UV, IR, MS, and NMR have each provided game-changing advances; the latest such advance is genomics. All natural products have a genetic basis, and the ability to obtain and interpret genomic information for structure elucidation is increasingly available at low cost to non-specialists. In this review, we describe the value of genomics as a structural elucidation technique, especially from the perspective of the natural product chemist approaching an unknown metabolite. Herein we first introduce the databases and programs of interest to the natural products chemist, with an emphasis on those currently most suited for general usability. We describe strategies for linking observed natural product-linked phenotypes to their corresponding gene clusters. We then discuss techniques for extracting structural information from genes, illustrated with numerous case examples. We also provide an analysis of the biases and limitations of the field with recommendations for future development. Our overview is not only aimed at biologically-oriented researchers already at ease with bioinformatic techniques, but also, in particular, at natural product, organic, and/or medicinal chemists not previously familiar with genomic techniques.

  2. HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING

    Energy Technology Data Exchange (ETDEWEB)

    Dennis Dalrymple

    2004-06-01

    This final report describes the objectives, technical approach, results and conclusions for a project funded by the U.S. Department of Energy to test a hybrid sulfur recovery process for natural gas upgrading. The process concept is a configuration of CrystaTech, Inc.'s CrystaSulf{reg_sign} process which utilizes a direct oxidation catalyst upstream of the absorber tower to oxidize a portion of the inlet hydrogen sulfide (H{sub 2}S) to sulfur dioxide (SO{sub 2}) and elemental sulfur. This hybrid configuration of CrystaSulf has been named CrystaSulf-DO and represents a low-cost option for direct treatment of natural gas streams to remove H{sub 2}S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day and more. This hybrid process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both onshore and offshore applications. CrystaSulf is a nonaqueous sulfur recovery process that removes H{sub 2}S from gas streams and converts it to elemental sulfur. In CrystaSulf, H{sub 2}S in the inlet gas is reacted with SO{sub 2} to make elemental sulfur according to the liquid phase Claus reaction: 2H{sub 2}S + SO{sub 2} {yields} 2H{sub 2}O + 3S. The SO{sub 2} for the reaction can be supplied from external sources by purchasing liquid SO{sub 2} and injecting it into the CrystaSulf solution, or produced internally by converting a portion of the inlet gas H{sub 2}S to SO{sub 2} or by burning a portion of the sulfur produced to make SO{sub 2}. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, the needed SO{sub 2} is produced by placing a bed of direct oxidation catalyst in the inlet gas stream to oxidize

  3. Hybrid Molten Bed Gasifier for High Hydrogen Syngas Production

    Energy Technology Data Exchange (ETDEWEB)

    Rue, David [Gas Technology Institute, Des Plaines, IL (United States)

    2017-05-23

    The techno-economic analyses of the hybrid molten bed gasification technology and laboratory testing of the HMB process were carried out in this project by the Gas Technology Institute and partner Nexant, Inc. under contract with the US Department of Energy’s National Energy Technology Laboratory. This report includes the results of two complete IGCC and Fischer-Tropsch TEA analyses comparing HMB gasification with the Shell slagging gasification process as a base case. Also included are the results of the laboratory simulation tests of the HMB process using Illinois #6 coal fed along with natural gas, two different syngases, and steam. Work in this 18-month project was carried out in three main Tasks. Task 2 was completed first and involved modeling, mass and energy balances, and gasification process design. The results of this work were provided to Nexant as input to the TEA IGCC and FT configurations studied in detail in Task 3. The results of Task 2 were also used to guide the design of the laboratory-scale testing of the HMB concept in the submerged combustion melting test facility in GTI’s industrial combustion laboratory. All project work was completed on time and budget. A project close-out meeting reviewing project results was conducted on April 1, 2015 at GTI in Des Plaines, IL. The hybrid molten bed gasification process techno-economic analyses found that the HMB process is both technically and economically attractive compared with the Shell entrained flow gasification process. In IGCC configuration, HMB gasification provides both efficiency and cost benefits. In Fischer-Tropsch configuration, HMB shows small benefits, primarily because even at current low natural gas prices, natural gas is more expensive than coal on an energy cost basis. HMB gasification was found in the TEA to improve the overall IGCC economics as compared to the coal only Shell gasification process. Operationally, the HMB process proved to be robust and easy to operate. The burner

  4. Psychoactive natural products: overview of recent developments

    Directory of Open Access Journals (Sweden)

    István Ujváry

    2014-03-01

    Full Text Available Natural psychoactive substances have fascinated the curious mind of shamans, artists, scholars and laymen since antiquity. During the twentieth century, the chemical composition of the most important psychoactive drugs, that is opium, cannabis, coca and "magic mushrooms", has been fully elucidated. The mode of action of the principal ingredients has also been deciphered at the molecular level. In the past two decades, the use of herbal drugs, such as kava, kratom and Salvia divinorum, began to spread beyond their traditional geographical and cultural boundaries. The aim of the present paper is to briefly summarize recent findings on the psychopharmacology of the most prominent psychoactive natural products. Current knowledge on a few lesser-known drugs, including bufotenine, glaucine, kava, betel, pituri, lettuce opium and kanna is also reviewed. In addition, selected cases of alleged natural (or semi-natural products are also mentioned.

  5. Psychoactive natural products: overview of recent developments.

    Science.gov (United States)

    Ujváry, István

    2014-01-01

    Natural psychoactive substances have fascinated the curious mind of shamans, artists, scholars and laymen since antiquity. During the twentieth century, the chemical composition of the most important psychoactive drugs, that is opium, cannabis, coca and "magic mushrooms", has been fully elucidated. The mode of action of the principal ingredients has also been deciphered at the molecular level. In the past two decades, the use of herbal drugs, such as kava, kratom and Salvia divinorum, began to spread beyond their traditional geographical and cultural boundaries. The aim of the present paper is to briefly summarize recent findings on the psychopharmacology of the most prominent psychoactive natural products. Current knowledge on a few lesser-known drugs, including bufotenine, glaucine, kava, betel, pituri, lettuce opium and kanna is also reviewed. In addition, selected cases of alleged natural (or semi-natural) products are also mentioned.

  6. Review: Natural products from Genus Selaginella (Selaginellaceae

    Directory of Open Access Journals (Sweden)

    AHMAD DWI SETYAWAN

    2011-01-01

    Full Text Available Setyawan AD. 2011. Natural products from Genus Selaginella (Selaginellaceae. Nusantara Bioscience 3: 44-58. Selaginella is a potent medicinal-stuff, which contains diverse of natural products such as alkaloid, phenolic (flavonoid, and terpenoid. This species is traditionally used to cure several diseases especially for wound, after childbirth, and menstrual disorder. Biflavonoid, a dimeric form of flavonoids, is the most valuable natural products of Selaginella, which constituted at least 13 compounds, namely amentoflavone, 2',8''-biapigenin, delicaflavone, ginkgetin, heveaflavone, hinokiflavone, isocryptomerin, kayaflavone, ochnaflavone, podocarpusflavone A, robustaflavone, sumaflavone, and taiwaniaflavone. Ecologically, plants use biflavonoid to response environmental condition such as defense against pests, diseases, herbivory, and competitions; while human medically use biflavonoid especially for antioxidant, anti-inflammatory, and anti carcinogenic. Selaginella also contains valuable disaccharide, namely trehalose that has long been known for protecting from desiccation and allows surviving severe environmental stress. The compound has very prospects as molecular stabilizer in the industries based bioresources.

  7. Countercurrent Separation of Natural Products: An Update

    Science.gov (United States)

    2015-01-01

    This work assesses the current instrumentation, method development, and applications in countercurrent chromatography (CCC) and centrifugal partition chromatography (CPC), collectively referred to as countercurrent separation (CCS). The article provides a critical review of the CCS literature from 2007 since our last review (J. Nat. Prod.2008, 71, 1489–1508), with a special emphasis on the applications of CCS in natural products research. The current state of CCS is reviewed in regard to three continuing topics (instrumentation, solvent system development, theory) and three new topics (optimization of parameters, workflow, bioactivity applications). The goals of this review are to deliver the necessary background with references for an up-to-date perspective of CCS, to point out its potential for the natural product scientist, and thereby to induce new applications in natural product chemistry, metabolome, and drug discovery research involving organisms from terrestrial and marine sources. PMID:26177360

  8. Early State Research on Antifungal Natural Products

    Directory of Open Access Journals (Sweden)

    Melyssa Negri

    2014-03-01

    Full Text Available Nosocomial infections caused by fungi have increased greatly in recent years, mainly due to the rising number of immunocompromised patients. However, the available antifungal therapeutic arsenal is limited, and the development of new drugs has been slow. Therefore, the search for alternative drugs with low resistance rates and fewer side effects remains a major challenge. Plants produce a variety of medicinal components that can inhibit pathogen growth. Studies of plant species have been conducted to evaluate the characteristics of natural drug products, including their sustainability, affordability, and antimicrobial activity. A considerable number of studies of medicinal plants and alternative compounds, such as secondary metabolites, phenolic compounds, essential oils and extracts, have been performed. Thus, this review discusses the history of the antifungal arsenal, surveys natural products with potential antifungal activity, discusses strategies to develop derivatives of natural products, and presents perspectives on the development of novel antifungal drug candidates.

  9. Multivariate analysis applied to tomato hybrid production.

    Science.gov (United States)

    Balasch, S; Nuez, F; Palomares, G; Cuartero, J

    1984-11-01

    Twenty characters were measured on 60 tomato varieties cultivated in the open-air and in polyethylene plastic-house. Data were analyzed by means of principal components, factorial discriminant methods, Mahalanobis D(2) distances and principal coordinate techniques. Factorial discriminant and Mahalanobis D(2) distances methods, both of which require collecting data plant by plant, lead to similar conclusions as the principal components method that only requires taking data by plots. Characters that make up the principal components in both environments studied are the same, although the relative importance of each one of them varies within the principal components. By combining information supplied by multivariate analysis with the inheritance mode of characters, crossings among cultivars can be experimented with that will produce heterotic hybrids showing characters within previously established limits.

  10. Natural hybridization between Paragonimus bangkokensis and Paragonimus harinasutai.

    Science.gov (United States)

    Doanh, Pham Ngoc; Guo, Zhihong; Nonaka, Nariaki; Horii, Yoichiro; Nawa, Yukifumi

    2013-06-01

    Paragonimus bangkokensis and Paragonimus harinasutai, which are morphologically distinguishable species, often co-infect in the same crab intermediate hosts. Recent molecular phylogenetic analyses revealed that these two species are genetically close to each other and are considered as the sister species. While we have been studying Paragonimus adult worms obtained from the lungs of a cat experimentally infected with Paragonimus metacercariae which were morphologically identified as P. harinasutai collected from central Viet Nam, one out of 6 adult worms has grouped cuticular spines, which is a feature of P. bangkokensis. By molecular analyses, the CO1 sequence of this specimen was identical with that of P. bangkokensis, but the ITS2 and the D2 region of 28S rDNA sequences showed a two peak pattern. Then, PCR products of the ITS2 and the D2 region of 28S rDNA sequences were ligated to TOPO vector and subcloned to determine the heterozygosity. Two types of sequences were obtained from each ITS2 and D2 region of 28S; one was identical with P. harinasutai and the other with P. bangkokensis. Taking all these morphological and molecular data together, we identified this adult worm as a hybrid specimen of P. bangkokensis and P. harinasutai.

  11. Anti-Inflammatory Activity of Natural Products

    Directory of Open Access Journals (Sweden)

    Abdullatif Azab

    2016-10-01

    Full Text Available This article presents highlights of the published literature regarding the anti-inflammatory activities of natural products. Many review articles were published in this regard, however, most of them have presented this important issue from a regional, limited perspective. This paper summarizes the vast range of review and research articles that have reported on the anti-inflammatory effects of extracts and/or pure compounds derived from natural products. Moreover, this review pinpoints some interesting traditionally used medicinal plants that were not investigated yet.

  12. Viewing hybrid systems as products of control systems and automata

    Science.gov (United States)

    Grossman, R. L.; Larson, R. G.

    1992-01-01

    The purpose of this note is to show how hybrid systems may be modeled as products of nonlinear control systems and finite state automata. By a hybrid system, we mean a network of consisting of continuous, nonlinear control system connected to discrete, finite state automata. Our point of view is that the automata switches between the control systems, and that this switching is a function of the discrete input symbols or letters that it receives. We show how a nonlinear control system may be viewed as a pair consisting of a bialgebra of operators coding the dynamics, and an algebra of observations coding the state space. We also show that a finite automata has a similar representation. A hybrid system is then modeled by taking suitable products of the bialgebras coding the dynamics and the observation algebras coding the state spaces.

  13. On exotic hybrid meson production in gamma* gamma collisions

    CERN Document Server

    Anikin, I V; Szymanowski, L; Teryaev, O V; Wallon, S

    2006-01-01

    We present a theoretical study of exotic hybrid meson (JPC=1-+) production in photon-photon collisions where one of the photons is deeply virtual, including twist 2 and twist 3 contributions. We calculate the cross section of this process which turns out to be large enough to imply sizeable counting rates in the present high luminosity electron-positron colliders. We emphasize theimportance of the pi eta decay channel for the detection of the hybrid meson candidate pi_1(1400) and calculate the cross section and the angular distribution for pi eta pair production in the unpolarized case. This angular distribution is a useful tool for disentangling the hybrid meson signal from the background. Finally, we calculate the single spin asymmetry associated with one initial longitudinally polarized lepton.

  14. An automated Genomes-to-Natural Products platform (GNP) for the discovery of modular natural products.

    Science.gov (United States)

    Johnston, Chad W; Skinnider, Michael A; Wyatt, Morgan A; Li, Xiang; Ranieri, Michael R M; Yang, Lian; Zechel, David L; Ma, Bin; Magarvey, Nathan A

    2015-09-28

    Bacterial natural products are a diverse and valuable group of small molecules, and genome sequencing indicates that the vast majority remain undiscovered. The prediction of natural product structures from biosynthetic assembly lines can facilitate their discovery, but highly automated, accurate, and integrated systems are required to mine the broad spectrum of sequenced bacterial genomes. Here we present a genome-guided natural products discovery tool to automatically predict, combinatorialize and identify polyketides and nonribosomal peptides from biosynthetic assembly lines using LC-MS/MS data of crude extracts in a high-throughput manner. We detail the directed identification and isolation of six genetically predicted polyketides and nonribosomal peptides using our Genome-to-Natural Products platform. This highly automated, user-friendly programme provides a means of realizing the potential of genetically encoded natural products.

  15. Plants as natural antioxidants for meat products

    Science.gov (United States)

    Tomović, V.; Jokanović, M.; Šojić, B.; Škaljac, S.; Ivić, M.

    2017-09-01

    The meat industry is demanding antioxidants from natural sources to replace synthetic antioxidants because of the negative health consequences or beliefs regarding some synthetic ones. Plants materials provide good alternatives. Spices and herbs, generally used for their flavouring characteristics, can be added to meat products in various forms: whole, ground, or as isolates from their extracts. These natural antioxidants contain some active compounds, which exert antioxidative potential in meat products. This antioxidant activity is most often due to phenolic acids, phenolic diterpenes, flavonoids and volatile oils. Each of these compounds often has strong H-donating activity, thus making them extremely effective antioxidants; some compounds can chelate metals and donate H to oxygen radicals, thus slowing oxidation via two mechanisms. Numerous studies have demonstrated the efficacy of natural antioxidants when used in meat products. Based on this literature review, it can be concluded that natural antioxidants are added to fresh and processed meat and meat products to delay, retard, or prevent lipid oxidation, retard development of off-flavours (rancidity), improve colour stability, improve microbiological quality and extend shelf-life, without any damage to the sensory or nutritional properties.

  16. Chocolate: A Marvelous Natural Product of Chemistry

    Science.gov (United States)

    Tannenbaum, Ginger

    2004-01-01

    The study of chocolate, a natural product, can be beneficial for the chemistry students as they ask frequently about the relevancy of their chemistry classes. The history of chocolate, its chemical and physical changes during processing, its composition, different crystalline forms, tempering and its viscosity are discussed.

  17. Standardization for natural product synthetic biology

    NARCIS (Netherlands)

    Zhao, Huimin; Medema, Marnix H.

    2016-01-01

    Standardization is one of the foundational features of modern-day engineering, and the use of standardized parts and processes is a key element that distinguishes bona fide synthetic biology from traditional genetic engineering. Here, we discuss the role of standardization in natural product

  18. Marine natural products as prototype agrochemical agents.

    Science.gov (United States)

    Peng, Jiangnan; Shen, Xiaoyu; El Sayed, Khalid A; Dunbar, D Charles; Perry, Tony L; Wilkins, Scott P; Hamann, Mark T; Bobzin, Steve; Huesing, Joseph; Camp, Robin; Prinsen, Mike; Krupa, Dan; Wideman, Margaret A

    2003-04-09

    In the interest of identifying new leads that could serve as prototype agrochemical agents, 18 structurally diverse marine-derived compounds were examined for insecticidal, herbicidal, and fungicidal activities. Several new classes of compounds have been shown to be insecticidal, herbicidal, and fungicidal, which suggests that marine natural products represent an intriguing source for the discovery of new agrochemical agents.

  19. Marine Natural Products as Prototype Agrochemical Agents

    OpenAIRE

    Peng, Jiangnan; Shen, Xiaoyu; Khalid A. El Sayed; Dunbar, D. C Harles; Perry, Tony L.; Wilkins, Scott P.; Hamann, Mark T.; Bobzin, Steve; Huesing, Joseph; Camp, Robin; Prinsen, Mike; Krupa, Dan; Wideman, Margaret A.

    2003-01-01

    In the interest of identifying new leads that could serve as prototype agrochemical agents, 18 structurally diverse marine-derived compounds were examined for insecticidal, herbicidal, and fungicidal activities. Several new classes of compounds have been shown to be insecticidal, herbicidal, and fungicidal, which suggests that marine natural products represent an intriguing source for the discovery of new agrochemical agents.

  20. Natural products – learning chemistry from plants

    NARCIS (Netherlands)

    Staniek, A.; Bouwmeester, H.J.; Fraser, P.D.; Kayser, O.; Martens, S.; Tissier, A.; Krol, van der A.R.; Wessjohann, L.; Warzecha, H.

    2014-01-01

    Plant natural products (PNPs) are unique in that they represent a vast array of different structural features, ranging from relatively simple molecules to very complex ones. Given the fact that many plant secondary metabolites exhibit profound biological activity, they are frequently used as

  1. Natural products – learning chemistry from plants

    NARCIS (Netherlands)

    Staniek, A.; Bouwmeester, H.J.; Fraser, P.D.; Kayser, O.; Martens, S.; Tissier, A.; Krol, van der A.R.; Wessjohann, L.; Warzecha, H.

    2014-01-01

    Plant natural products (PNPs) are unique in that they represent a vast array of different structural features, ranging from relatively simple molecules to very complex ones. Given the fact that many plant secondary metabolites exhibit profound biological activity, they are frequently used as fragran

  2. Natural products from microbes associated with insects

    DEFF Research Database (Denmark)

    Beemelmanns, Christine; Guo, Huijuan; Rischer, Maja;

    2016-01-01

    Here we review discoveries of secondary metabolites from microbes associated with insects. We mainly focus on natural products, where the ecological role has been at least partially elucidated, and/or the pharmaceutical properties evaluated, and on compounds with unique structural features. We...

  3. Computational approaches to natural product discovery

    NARCIS (Netherlands)

    Medema, M.H.; Fischbach, M.A.

    2015-01-01

    Starting with the earliest Streptomyces genome sequences, the promise of natural product genome mining has been captivating: genomics and bioinformatics would transform compound discovery from an ad hoc pursuit to a high-throughput endeavor. Until recently, however, genome mining has advanced natura

  4. Flow chemistry syntheses of natural products.

    Science.gov (United States)

    Pastre, Julio C; Browne, Duncan L; Ley, Steven V

    2013-12-07

    The development and application of continuous flow chemistry methods for synthesis is a rapidly growing area of research. In particular, natural products provide demanding challenges to this developing technology. This review highlights successes in the area with an emphasis on new opportunities and technological advances.

  5. Natural products in modern life science.

    Science.gov (United States)

    Bohlin, Lars; Göransson, Ulf; Alsmark, Cecilia; Wedén, Christina; Backlund, Anders

    2010-06-01

    With a realistic threat against biodiversity in rain forests and in the sea, a sustainable use of natural products is becoming more and more important. Basic research directed against different organisms in Nature could reveal unexpected insights into fundamental biological mechanisms but also new pharmaceutical or biotechnological possibilities of more immediate use. Many different strategies have been used prospecting the biodiversity of Earth in the search for novel structure-activity relationships, which has resulted in important discoveries in drug development. However, we believe that the development of multidisciplinary incentives will be necessary for a future successful exploration of Nature. With this aim, one way would be a modernization and renewal of a venerable proven interdisciplinary science, Pharmacognosy, which represents an integrated way of studying biological systems. This has been demonstrated based on an explanatory model where the different parts of the model are explained by our ongoing research. Anti-inflammatory natural products have been discovered based on ethnopharmacological observations, marine sponges in cold water have resulted in substances with ecological impact, combinatory strategy of ecology and chemistry has revealed new insights into the biodiversity of fungi, in depth studies of cyclic peptides (cyclotides) has created new possibilities for engineering of bioactive peptides, development of new strategies using phylogeny and chemography has resulted in new possibilities for navigating chemical and biological space, and using bioinformatic tools for understanding of lateral gene transfer could provide potential drug targets. A multidisciplinary subject like Pharmacognosy, one of several scientific disciplines bridging biology and chemistry with medicine, has a strategic position for studies of complex scientific questions based on observations in Nature. Furthermore, natural product research based on intriguing scientific

  6. Natural production of biological optical systems

    Science.gov (United States)

    Choi, Seung Ho; Kim, Young L.

    2015-03-01

    Synthesis and production in nature often provide ideas to design and fabricate advanced biomimetic photonic materials and structures, leading to excellent physical properties and enhanced performance. In addition, the recognition and utilization of natural or biological substances have been typical routes to develop biocompatible and biodegradable materials for medical applications. In this respect, biological lasers utilizing such biomaterials and biostructures have been received considerable attention, given a variety of implications and potentials for bioimaging, biosensing, implantation, and therapy. However, without relying on industrial facilities, eco-friendly massive production of such optical components or systems has not yet been investigated. We show examples of bioproduction of biological lasers using agriculture and fisheries. We anticipate that such approaches will open new possibilities for scalable eco-friendly `green' production of biological photonics components and systems.

  7. [Status of libraries and databases for natural products at abroad].

    Science.gov (United States)

    Zhao, Li-Mei; Tan, Ning-Hua

    2015-01-01

    For natural products are one of the important sources for drug discovery, libraries and databases of natural products are significant for the development and research of natural products. At present, most of compound libraries at abroad are synthetic or combinatorial synthetic molecules, resulting to access natural products difficult; for information of natural products are scattered with different standards, it is difficult to construct convenient, comprehensive and large-scale databases for natural products. This paper reviewed the status of current accessing libraries and databases for natural products at abroad and provided some important information for the development of libraries and database for natural products.

  8. Shape based assignment tests suggest transgressive phenotypes in natural sculpin hybrids (Teleostei, Scorpaeniformes, Cottidae

    Directory of Open Access Journals (Sweden)

    Sheets H David

    2005-06-01

    Full Text Available Abstract Background Hybridization receives attention because of the potential role that it may play in generating evolutionary novelty. An explanation for the emergence of novel phenotypes is given by transgressive segregation, which, if frequent, would imply an important evolutionary role for hybridization. This process is still rarely studied in natural populations as samples of recent hybrids and their parental populations are needed. Further, the detection of transgressive segregation requires phenotypes that can be easily quantified and analysed. We analyse variability in body shape of divergent populations of European sculpins (Cottus gobio complex as well as natural hybrids among them. Results A distance-based method is developed to assign unknown specimens to known groups based on morphometric data. Apparently, body shape represents a highly informative set of characters that parallels the discriminatory power of microsatellite markers in our study system. Populations of sculpins are distinct and "unknown" specimens can be correctly assigned to their source population based on body shape. Recent hybrids are intermediate along the axes separating their parental groups but display additional differentiation that is unique and coupled with the hybrid genetic background. Conclusion There is a specific hybrid shape component in natural sculpin hybrids that can be best explained by transgressive segregation. This inference of how hybrids differ from their ancestors provides basic information for future evolutionary studies. Furthermore, our approach may serve to assign candidate specimens to their source populations based on morphometric data and help in the interpretation of population differentiation.

  9. Human disturbance causes the formation of a hybrid swarm between two naturally sympatric fish species.

    Science.gov (United States)

    Hasselman, Daniel J; Argo, Emily E; McBride, Meghan C; Bentzen, Paul; Schultz, Thomas F; Perez-Umphrey, Anna A; Palkovacs, Eric P

    2014-03-01

    Most evidence for hybrid swarm formation stemming from anthropogenic habitat disturbance comes from the breakdown of reproductive isolation between incipient species, or introgression between allopatric species following secondary contact. Human impacts on hybridization between divergent species that naturally occur in sympatry have received considerably less attention. Theory predicts that reinforcement should act to preserve reproductive isolation under such circumstances, potentially making reproductive barriers resistant to human habitat alteration. Using 15 microsatellites, we examined hybridization between sympatric populations of alewife (Alosa pseudoharengus) and blueback herring (A. aestivalis) to test whether the frequency of hybridization and pattern of introgression have been impacted by the construction of a dam that isolated formerly anadromous populations of both species in a landlocked freshwater reservoir. The frequency of hybridization and pattern of introgression differed markedly between anadromous and landlocked populations. The rangewide frequency of hybridization among anadromous populations was generally 0-8%, whereas all landlocked individuals were hybrids. Although neutral introgression was observed among anadromous hybrids, directional introgression leading to increased prevalence of alewife genotypes was detected among landlocked hybrids. We demonstrate that habitat alteration can lead to hybrid swarm formation between divergent species that naturally occur sympatrically, and provide empirical evidence that reinforcement does not always sustain reproductive isolation under such circumstances.

  10. Automated genome mining for natural products

    Directory of Open Access Journals (Sweden)

    Zajkowski James

    2009-06-01

    Full Text Available Abstract Background Discovery of new medicinal agents from natural sources has largely been an adventitious process based on screening of plant and microbial extracts combined with bioassay-guided identification and natural product structure elucidation. Increasingly rapid and more cost-effective genome sequencing technologies coupled with advanced computational power have converged to transform this trend toward a more rational and predictive pursuit. Results We have developed a rapid method of scanning genome sequences for multiple polyketide, nonribosomal peptide, and mixed combination natural products with output in a text format that can be readily converted to two and three dimensional structures using conventional software. Our open-source and web-based program can assemble various small molecules composed of twenty standard amino acids and twenty two other chain-elongation intermediates used in nonribosomal peptide systems, and four acyl-CoA extender units incorporated into polyketides by reading a hidden Markov model of DNA. This process evaluates and selects the substrate specificities along the assembly line of nonribosomal synthetases and modular polyketide synthases. Conclusion Using this approach we have predicted the structures of natural products from a diverse range of bacteria based on a limited number of signature sequences. In accelerating direct DNA to metabolomic analysis, this method bridges the interface between chemists and biologists and enables rapid scanning for compounds with potential therapeutic value.

  11. Regulation of natural health products in Canada.

    Science.gov (United States)

    Smith, Alysyn; Jogalekar, Sumedha; Gibson, Adam

    2014-12-02

    In Canada, all natural health products (NHPs) are regulated by Health Canada (HC) under the Food and Drugs Act and the Natural Health Product Regulations. All authorized products undergo pre-market assessment for safety, efficacy and quality and the degree of pre-market oversight varies depending on the risk of the product. In Canada, over 70,000 products have been authorized for sale and over 2000 sites have been licensed to produce NHPs. In the management of NHPs on the Canadian market, HC employs a number of active and collaborative methods to address the most common issues such as contamination, adulteration and deceptive or misleading advertising practices. HC is currently evolving its approaches to NHPs to recognize them as part of the larger group of health products available without a prescription. As such, the regulatory responsibility for all over-the-counter (OTC) drugs, including non-prescription drugs and NHPs, has been transferred to a single federal division. As a result of this transition a number of benefits are being realized with respect to government efficiency, clarity for industry, support for new innovations and consolidated government interactions with the Canadian market. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. In silico Design of "Un-Natural" Natural Products

    Directory of Open Access Journals (Sweden)

    Zucko; J. ...(et al.

    2008-05-01

    Full Text Available Polyketides and non-ribosomal peptides represent a large class of structurally diverse natural products much studied over recent years because the enzymes that synthesise them, the modular polyketide synthases (PKSs and the non-ribosomal peptide synthetases (NRPSs, share striking architectural similarities that can be exploited to generate "un-natural" natural products. PKS and NRPS proteins are multifunctional, composed of a co-linear arrangement of discrete protein domains representing each enzymic activity needed for chain elongation using either carboxylic acid or amino acid building blocks. Each domain is housed within larger modules which form the complex. Polyketide and peptide antibiotics, antifungals, antivirals, cytostatics, immunosuppressants, antihypertensives, antidiabetics, antimalarials and anticholesterolemics are in clinical use. Of commercial importance are also polyketide and peptide antiparasitics, coccidiostatics,animal growth promoters and natural insecticides.Polyketides are assembled through serial condensations of activated coenzyme-A thioester monomers derived from simple organic acids such as acetate, propionate and butyrate. The choice of organic acid allows the introduction of different chiral centres into the polyketide backbone. The active sites required for condensation include an acyltransferase (AT, an acyl carrier protein (ACP and a ß-ketoacylsynthase (KS. Each condensation results in a ß-keto group that undergoes all, some or none of a series of processing steps. Active sites that perform these reactions are contained within the following domains; ketoreductase (KR, dehydratase (DH and an enoylreductase (ER. The absence of any ß-keto processing results in the incorporation of a ketone group into the growing polyketide chain, a KR alone gives rise to a hydroxyl moiety, a KR and DH produce an alkene, while the combination of KR, DH and ER domains lead to complete reduction to an alkane. Most often, the last

  13. Genome Size Variation in Central European Species of Cirsium (Compositae) and their Natural Hybrids

    OpenAIRE

    Bureš, Petr; Wang, Yi-Feng; Horová, Lucie; Suda, Jan

    2004-01-01

    • Background and Aims Nuclear DNA amounts of 12 diploid and one tetraploid taxa and 12 natural interspecific hybrids of Cirsium from 102 populations in the Czech Republic, Austria, Slovakia and Hungary were estimated.

  14. Utilization of Natural Products as Functional Feed

    Directory of Open Access Journals (Sweden)

    Stella Magdalena

    2013-03-01

    Full Text Available The use of antibiotics as feed additive improves performance in livestock. However, scientific data related to the use of antibiotics in feed merge spreading of bacterial resistance in animal and human bodies, therefore the usage of antibiotics in animal production is restricted. This condition raise the utilization of natural antibiotic as functional feed such as phytogenics (essential oil, flavonoid, saponin, and tannin, enzyme, probiotic, and prebiotic to improve the livestock’s performance, quality, and health. Functional feeds increase profitability in animal husbandry production and its use is feeds are expected to be functional foods that may have positive effects in human nutrition.

  15. (+-Discodermolide: A Marine Natural Product Against Cancer

    Directory of Open Access Journals (Sweden)

    Marcus Viníus Nora De Souza

    2004-01-01

    Full Text Available (+-Discodermolide was isolated in 1990 by Gunasekera et al. from the deep-water Caribbean sponge Discodermia dissoluta. It attacks cancer cells in a similar way to the successful cancer drug Taxol® that has become the best-selling anticancer drug in history. Taxol is also the first natural product described that stabilizes the microtubules involved in many aspects of cellular biology and that represent an important target of anticancer chemotherapeutics. However, (+-discodermolide appears to be far more potent than Taxol® against tumors that have developed multiple-drug resistance, with an IC50 in the low nanomolar range. Due to these excellent results, this natural product was licensed to Novartis Pharmaceutical Corporation in early 1998. The present review covers the history, biological activity, total synthesis, and synthetic analogs of (+-discodermolide.

  16. Trypanocidal Activity of Marine Natural Products

    Directory of Open Access Journals (Sweden)

    Amy J. Jones

    2013-10-01

    Full Text Available Marine natural products are a diverse, unique collection of compounds with immense therapeutic potential. This has resulted in these molecules being evaluated for a number of different disease indications including the neglected protozoan diseases, human African trypanosomiasis and Chagas disease, for which very few drugs are currently available. This article will review the marine natural products for which activity against the kinetoplastid parasites; Trypanosoma brucei brucei, T.b. rhodesiense and T. cruzi has been reported. As it is important to know the selectivity of a compound when evaluating its trypanocidal activity, this article will only cover molecules which have simultaneously been tested for cytotoxicity against a mammalian cell line. Compounds have been grouped according to their chemical structure and representative examples from each class were selected for detailed discussion.

  17. (+)-discodermolide: a marine natural product against cancer.

    Science.gov (United States)

    De Souza, Marcus Vinícius Nora

    2004-06-11

    (+)-discodermolide was isolated in 1990 by Gunasekera et al. from the deep-water Caribbean sponge Discodermia dissoluta. It attacks cancer cells in a similar way to the successful cancer drug Taxol that has become the best-selling anticancer drug in history. Taxol is also the first natural product described that stabilizes the microtubules involved in many aspects of cellular biology and that represent an important target of anticancer chemotherapeutics. However, (+)-discodermolide appears to be far more potent than Taxol against tumors that have developed multiple-drug resistance, with an IC50 in the low nanomolar range. Due to these excellent results, this natural product was licensed to Novartis Pharmaceutical Corporation in early 1998. The present review covers the history, biological activity, total synthesis, and synthetic analogs of (+)-discodermolide.

  18. Synthetic biological approaches to natural product biosynthesis.

    Science.gov (United States)

    Winter, Jaclyn M; Tang, Yi

    2012-10-01

    Small molecules produced in Nature possess exquisite chemical diversity and continue to be an inspiration for the development of new therapeutic agents. In their host organisms, natural products are assembled and modified using dedicated biosynthetic pathways. By rationally reprogramming and manipulating these pathways, unnatural metabolites containing enhanced structural features that were otherwise inaccessible can be obtained. Additionally, new chemical entities can be synthesized by developing the enzymes that carry out these complicated chemical reactions into biocatalysts. In this review, we will discuss a variety of combinatorial biosynthetic strategies, their technical challenges, and highlight some recent (since 2007) examples of rationally designed metabolites, as well as platforms that have been established for the production and modification of clinically important pharmaceutical compounds.

  19. Standardization for natural product synthetic biology.

    Science.gov (United States)

    Zhao, Huimin; Medema, Marnix H

    2016-08-27

    Standardization is one of the foundational features of modern-day engineering, and the use of standardized parts and processes is a key element that distinguishes bona fide synthetic biology from traditional genetic engineering. Here, we discuss the role of standardization in natural product synthetic biology, focusing on standardization of data on biosynthetic pathways and gene clusters, as well as the role of standardization in the process of biosynthetic gene cluster engineering.

  20. Natural Products as Sources for New Pesticides

    Science.gov (United States)

    2012-05-22

    A number of bio - chemical herbicides have been registered with the EPA since 1997. Horticultural vinegar, which consists of diluted aqueous solutions...However, this has not been the case for herbicides . Only one class of natural product-derived herbicide has been registered since 1997, namely, the...triketone herbicides . The discovery and development of these herbicides followed a fairly convoluted path that began in 1977 when Reed Gray at

  1. Natural cold pressed oils as cosmetic products

    Directory of Open Access Journals (Sweden)

    Małgorzata Ligęza

    2016-12-01

    Full Text Available Background. It seems that patients may ask general practitioners about natural cosmetics applied on the skin regarding their safety and suitability. Objectives. The aim of the study was to analyze natural cold pressed oils as potential cosmetic products. Material and methods. Cold pressed oils obtained from selected seeds and fruit stones were analyzed, including: chokeberry seed oil, blackcurrant seed oil, elderberry seed oil, raspberry seed oil, apricot seed oil, tomato seed oil, strawberry seed oil, broccoli seed oil, Nigella sativa seed oil, hemp oil, safflower seed oil, Silybum marianum seed oil and coconut oil. 80 adult volunteers assessed the cosmetic properties of the analyzed oils. Each of the volunteers tested 2 to 4 different oils, by applying them on the skin. In addition, patch tests with all analyzed oils were performed on 23 individuals. Results. The majority of tested oils were positively evaluated by the participants: in the opinion of the participants, oil extracted from safflower had the best appearance (100% positive opinions, coconut oil had the best smell (70% positive opinions, while black currant seed oil showed the best absorbency (85% positive opinions. No irritation was observed within the analyzed product group, albeit one allergic reaction to apricot seed oil was observed with patch testing. Conclusions . Based on the achieved results, it could be suggested that natural cold pressed oils can be applied to the skin as cosmetics. Our observations may be helpful for general practitioners when choosing natural cosmetics.

  2. Natural products from filamentous fungi and production by heterologous expression.

    Science.gov (United States)

    Alberti, Fabrizio; Foster, Gary D; Bailey, Andy M

    2017-01-01

    Filamentous fungi represent an incredibly rich and rather overlooked reservoir of natural products, which often show potent bioactivity and find applications in different fields. Increasing the naturally low yields of bioactive metabolites within their host producers can be problematic, and yield improvement is further hampered by such fungi often being genetic intractable or having demanding culturing conditions. Additionally, total synthesis does not always represent a cost-effective approach for producing bioactive fungal-inspired metabolites, especially when pursuing assembly of compounds with complex chemistry. This review aims at providing insights into heterologous production of secondary metabolites from filamentous fungi, which has been established as a potent system for the biosynthesis of bioactive compounds. Numerous advantages are associated with this technique, such as the availability of tools that allow enhanced production yields and directing biosynthesis towards analogues of the naturally occurring metabolite. Furthermore, a choice of hosts is available for heterologous expression, going from model unicellular organisms to well-characterised filamentous fungi, which has also been shown to allow the study of biosynthesis of complex secondary metabolites. Looking to the future, fungi are likely to continue to play a substantial role as sources of new pharmaceuticals and agrochemicals-either as producers of novel natural products or indeed as platforms to generate new compounds through synthetic biology.

  3. Isolation of bioactive natural products from myxomycetes.

    Science.gov (United States)

    Ishibashi, Masami

    2005-11-01

    The Myxomycetes (true slime molds) are an unusual group of primitive organisms that may be assigned to one of the lowest classes of eukaryotes. As their fruit bodies are very small and it is very difficult to collect much quantity of slime molds, few studies have been made on the chemistry of myxomycetes. Cultivation of the plasmodium of myxomycetes in a practical scale for natural products chemistry studies is known only for very limited species. Here is described a review on the recent results on isolation of bioactive natural products from myxomycetes obtained in these two years in the laboratories. Spore germination experiments were studied of hundreds of field-collected myxomycetes collected in Japan and succeeded in laboratory culture of plasmodia of several myxomycetes in a practical scale for natural products chemistry studies. As a result, pyrroloiminoquinones, polyene yellow pigments, and a peptide lactone from cultured plasmodia of Didymium iridis, Physarum rigidum and P. melleum, respectively were isolated. New naphthoquinone pigments, cycloanthranilylprolines, tyrosine-kinase inhibitory bisindoles, and a cytotoxic triterpenoid aldehyde lactone were also isolated from field-collected fruit bodies of Cribraria purpurea, Fuligo candida, Tubifera casparyi, and Tubifera dimorphotheca, respectively.

  4. Natural and Heterologous Production of Bacteriocins

    Science.gov (United States)

    Cintas, Luis M.; Herranz, Carmen; Hernández, Pablo E.

    Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, and their use as natural and nontoxic food preservatives has been the source of considerable interest for the research community. In addition, bacteriocins have been investigated for their potential use in human and veterinary applications and in the animal production field. In the native bacterial strain, most bacteriocins are synthesized as biologically inactive precursors, with N-terminal extensions, that are cleaved concomitantly during export of the bacteriocin by dedicated ABC transporters, or the general secretory pathway (GSP) or Sec-dependent pathway. However, a few bacteriocins are synthesized without an N-terminal extension, and others are circularized through a head-to-tail peptide bond, complicating the elucidation of their processing and transport across the cytoplasmic membrane. The high cost of synthetic bacteriocin synthesis and their low yields from many natural producers recommends the exploration of recombinant microbial systems for the heterologous production of bacteriocins. Other advantages of such systems include production of bacteriocins in safer hosts, increased bacteriocin production, control of bacteriocin gene expression, production of food ingredients with antimicrobial activity, construction of multibacteriocinogenic strains with a wider antagonistic spectrum, a better adaptation of the selected hosts to food environments, and providing antagonistic properties to lactic acid bacteria (LAB) used as starter, protective, or probiotic cultures. The recombinant production of bacteriocins mostly relies on the use of expression vectors that replicate in Gram-negative bacteria, Gram-positive bacteria, and yeasts, whereas the production of bacteriocins in heterologous LAB hosts may be essentially based on the expression of native biosynthetic genes, by exchanging or replacing leader peptides and/or dedicated processing and secretion systems (ABC transporters

  5. Generation of New Genotypic and Phenotypic Features in Artificial and Natural Yeast Hybrids

    Directory of Open Access Journals (Sweden)

    Walter P. Pfliegler

    2014-01-01

    Full Text Available Evolution and genome stabilization have mostly been studied on the Saccharomyces hybrids isolated from natural and alcoholic fermentation environments. Genetic and phenotypic properties have usually been compared to the laboratory and reference strains, as the true ancestors of the natural hybrid yeasts are unknown. In this way the exact impact of different parental fractions on the genome organization or metabolic activity of the hybrid yeasts is difficult to resolve completely. In the present work the evolution of geno- and phenotypic properties is studied in the interspecies hybrids created by the cross-breeding of S. cerevisiae with S. uvarum or S. kudriavzevii auxotrophic mutants. We hypothesized that the extent of genomic alterations in S. cerevisiae × S. uvarum and S. cerevisiae × S. kudriavzevii should affect the physiology of their F1 offspring in different ways. Our results, obtained by amplified fragment length polymorphism (AFLP genotyping and karyotyping analyses, showed that both subgenomes of the S. cerevisiae x S. uvarum and of S. cerevisiae × S. kudriavzevii hybrids experienced various modifications. However, the S. cerevisiae × S. kudriavzevii F1 hybrids underwent more severe genomic alterations than the S. cerevisiae × S. uvarum ones. Generation of the new genotypes also influenced the physiological performances of the hybrids and the occurrence of novel phenotypes. Significant differences in carbohydrate utilization and distinct growth dynamics at increasing concentrations of sodium chloride, urea and miconazole were observed within and between the S. cerevisiae × S. uvarum and S. cerevisiae × S. kudriavzevii hybrids. Parental strains also demonstrated different contributions to the final metabolic outcomes of the hybrid yeasts. A comparison of the genotypic properties of the artificial hybrids with several hybrid isolates from the wine-related environments and wastewater demonstrated a greater genetic variability of

  6. Introgressive hybridization as a promoter of genome reshuffling in natural homoploid fish hybrids (Cyprinidae, Leuciscinae).

    Science.gov (United States)

    Pereira, C S A; Aboim, M A; Ráb, P; Collares-Pereira, M J

    2014-03-01

    Understanding the mechanisms underlying diversification and speciation by introgressive hybridization is currently one of the major challenges in evolutionary biology. Here, the analysis of hybridization between two pairs of Iberian Leuciscinae provided new data on independent hybrid zones involving Achondrostoma oligolepis (AOL) and Pseudochondrostoma duriense (PDU), and confirmed the occurrence of hybrids between AOL and Pseudochondrostoma polylepis (PPO). A multilevel survey combining morphological, genetic and cytogenomic markers on a vast population screening successfully sorted the selected fishes as admixed. Results were similar in both AOL × PDU and AOL × PPO systems. Overall, hybrid morphotypes, cytogenomic data and genetic profiling indicated preferential backcrossing and suggested AOL as a major genomic contributor. Moreover, results implied AOL as more permissive to introgression than PDU or PPO. Although PDU- and PPO-like individuals appeared more resilient to genome modifications, AOL appeared to be more involved and affected by the ongoing hybridization events, as chromosomal translocations were only found in AOL-like individuals. All hybrids analysed evidenced extensive ribosomal DNA (rDNA) polymorphism that was not found in parental species, but usually seen falling within the range of possible parental combinations. Yet, transgressive phenotypes that cannot be explained by normal recombination, including more rDNA clusters than expected or the occurrence of syntenic rDNAs, were also detected. Present results proved rapid genomic evolution providing the genetic novelty for species to persist. In addition, although the ultimate consequences of such apparently extensive and recurrent events remain unknown, modern genome-wide methodologies are of great promise towards answering questions concerning the causes, dynamics and impacts of hybridization.

  7. Natural and Anthropogenic Hybridization in Two Species of Eastern Brazilian Marmosets (Callithrix jacchus and C. penicillata)

    Science.gov (United States)

    Malukiewicz, Joanna; Boere, Vanner; Fuzessy, Lisieux F.; Grativol, Adriana D.; de Oliveira e Silva, Ita; Pereira, Luiz C. M.; Ruiz-Miranda, Carlos R.; Valença, Yuri M.; Stone, Anne C.

    2015-01-01

    Animal hybridization is well documented, but evolutionary outcomes and conservation priorities often differ for natural and anthropogenic hybrids. Among primates, an order with many endangered species, the two contexts can be hard to disentangle from one another, which carries important conservation implications. Callithrix marmosets give us a unique glimpse of genetic hybridization effects under distinct natural and human-induced contexts. Here, we use a 44 autosomal microsatellite marker panel to examine genome-wide admixture levels and introgression at a natural C. jacchus and C. penicillata species border along the São Francisco River in NE Brazil and in an area of Rio de Janeiro state where humans introduced these species exotically. Additionally, we describe for the first time autosomal genetic diversity in wild C. penicillata and expand previous C. jacchus genetic data. We characterize admixture within the natural zone as bimodal where hybrid ancestry is biased toward one parental species or the other. We also show evidence that São Francisco River islands are gateways for bidirectional gene flow across the species border. In the anthropogenic zone, marmosets essentially form a hybrid swarm with intermediate levels of admixture, likely from the absence of strong physical barriers to interspecific breeding. Our data show that while hybridization can occur naturally, the presence of physical, even if leaky, barriers to hybridization is important for maintaining species genetic integrity. Thus, we suggest further study of hybridization under different contexts to set well informed conservation guidelines for hybrid populations that often fit somewhere between “natural” and “man-made.” PMID:26061111

  8. Optical image encryption using Kronecker product and hybrid phase masks

    Science.gov (United States)

    Kumar, Ravi; Bhaduri, Basanta

    2017-10-01

    In this paper, we propose a new technique for security enhancement in optical image encryption system. In this technique we have used the Kronecker product of two random matrices along with the double random phase encoding (DRPE) scheme in the Fresnel domain for optical image encryption. The phase masks used here are different than the random masks used in conventional DRPE scheme. These hybrid phase masks are generated by using the combination of random phase masks and a secondary image. For encryption, the input image is first randomized and then the DRPE in the Fresnel domain is performed using the hybrid phase masks. Secondly, the Kronecker product of two random matrices is multiplied with the DRPE output to get the final encoded image for transmission. The proposed technique consists of more unknown keys for enhanced security and robust against various attacks. The simulation results along with effects under various attacks are presented in support of the proposed technique.

  9. Natural products as potential anticonvulsants: caffeoylquinic acids.

    Science.gov (United States)

    Kim, Hyo Geun; Oh, Myung Sook

    2012-03-01

    Current anticonvulsant therapies are generally directed at symptomatic treatment by suppressing excitability within the brain. Consequently, they have adverse effects such as cognitive impairment, dependence, and abuse. The need for more effective and less toxic anticonvulsants has generated renewed interest in natural products for the treatment of convulsions. Caffeoylquinic acids (CQs) are naturally occurring phenolic acids that are distributed widely in plants. There has been increasing interest in the biological activities of CQs in diseases of the central nervous system. In this issue, Nugroho et al. give evidence for the anticonvulsive effect of a CQ-rich extract from Aster glehni Franchet et Sckmidt. They optimized the extract solvent conditions, resulting in high levels of CQs and peroxynitrite-scavenging activity. Then, they investigated the sedative and anticonvulsive effects in pentobarbital- and pentylenetetrazole-induced models in mice. The CQ-rich extract significantly inhibited tonic convulsions as assessed by onset time, tonic extent, and mortality. They suggested that the CQ-rich extract from A. glehni has potential for treating convulsions. This report provides preclinical data which may be used for the development of anticonvulsants from natural products.

  10. Pricing of Traffic Light Options and other Hybrid Products

    DEFF Research Database (Denmark)

    Kokholm, Thomas

    2009-01-01

    This paper considers derivatives with payoffs that depend on a stock index and underlying LIBOR rates. A traffic light option pricing formula is derived under lognormality assumptions on the underlying processes. The traffic light option is aimed at the Danish life and pension sector to help comp...... the pricing of a hybrid derivative known as the EUR Sage Note. The approach can be used to price many existing structured products....

  11. An Improved Synthesis of the Natural Product Isorhapontigenin

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    We have developed an alternative route to synthesize the natural product, isorhapotogenin . The synthetic product was characterized by IR and 1H-NMR in comparison with the corresponding natural product.

  12. Phylogenetic approaches to natural product structure prediction.

    Science.gov (United States)

    Ziemert, Nadine; Jensen, Paul R

    2012-01-01

    Phylogenetics is the study of the evolutionary relatedness among groups of organisms. Molecular phylogenetics uses sequence data to infer these relationships for both organisms and the genes they maintain. With the large amount of publicly available sequence data, phylogenetic inference has become increasingly important in all fields of biology. In the case of natural product research, phylogenetic relationships are proving to be highly informative in terms of delineating the architecture and function of the genes involved in secondary metabolite biosynthesis. Polyketide synthases and nonribosomal peptide synthetases provide model examples in which individual domain phylogenies display different predictive capacities, resolving features ranging from substrate specificity to structural motifs associated with the final metabolic product. This chapter provides examples in which phylogeny has proven effective in terms of predicting functional or structural aspects of secondary metabolism. The basics of how to build a reliable phylogenetic tree are explained along with information about programs and tools that can be used for this purpose. Furthermore, it introduces the Natural Product Domain Seeker, a recently developed Web tool that employs phylogenetic logic to classify ketosynthase and condensation domains based on established enzyme architecture and biochemical function.

  13. Microbial production of natural raspberry ketone.

    Science.gov (United States)

    Beekwilder, Jules; van der Meer, Ingrid M; Sibbesen, Ole; Broekgaarden, Mans; Qvist, Ingmar; Mikkelsen, Joern D; Hall, Robert D

    2007-10-01

    Raspberry ketone is an important compound for the flavour industry. It is frequently used in products such as soft drinks, sweets, puddings and ice creams. The compound can be produced by organic synthesis. Demand for "natural" raspberry ketone is growing considerably. However, this product is extremely expensive. Consequently, there is a remaining desire to better understand how raspberry ketone is synthesized in vivo, and which genes and enzymes are involved. With this information we will then be in a better position to design alternative production strategies such as microbial fermentation. This article focuses on the identification and application of genes potentially linked to raspberry ketone synthesis. We have isolated candidate genes from both raspberry and other plants, and these have been introduced into bacterial and yeast expression systems. Conditions have been determined that result in significant levels of raspberry ketone, up to 5 mg/L. These results therefore lay a strong foundation for a potentially renewable source of "natural" flavour compounds making use of plant genes.

  14. Naturally occurring hybrids of coral reef butterflyfishes have similar fitness compared to parental species

    Science.gov (United States)

    Hobbs, Jean-Paul A.; Pratchett, Morgan S.; Bay, Line K.; van Herwerden, Lynne

    2017-01-01

    Hybridisation can produce evolutionary novelty by increasing fitness and adaptive capacity. Heterosis, or hybrid vigour, has been documented in many plant and animal taxa, and is a notable consequence of hybridisation that has been exploited for decades in agriculture and aquaculture. On the contrary, loss of fitness in naturally occurring hybrid taxa has been observed in many cases. This can have negative consequences for the parental species involved (wasted reproductive effort), and has raised concerns for species conservation. This study evaluates the relative fitness of previously documented butterflyfish hybrids of the genus Chaetodon from the Indo-Pacific suture zone at Christmas Island. Histological examination confirmed the reproductive viability of Chaetodon hybrids. Examination of liver lipid content showed that hybrid body condition was not significantly different from parent species body condition. Lastly, size at age data revealed no difference in growth rates and asymptotic length between hybrids and parent species. Based on the traits measured in this study, naturally occurring hybrids of Chaetodon butterflyfishes have similar fitness to their parental species, and are unlikely to supplant parental species under current environmental conditions at the suture zone. However, given sufficient fitness and ongoing genetic exchange between the respective parental species, hybrids are likely to persist within the suture zone. PMID:28257492

  15. Genetic Basis for Spontaneous Hybrid Genome Doubling during Allopolyploid Speciation of Common Wheat Shown by Natural Variation Analyses of the Paternal Species

    Science.gov (United States)

    Matsuoka, Yoshihiro; Nasuda, Shuhei; Ashida, Yasuyo; Nitta, Miyuki; Tsujimoto, Hisashi; Takumi, Shigeo; Kawahara, Taihachi

    2013-01-01

    The complex process of allopolyploid speciation includes various mechanisms ranging from species crosses and hybrid genome doubling to genome alterations and the establishment of new allopolyploids as persisting natural entities. Currently, little is known about the genetic mechanisms that underlie hybrid genome doubling, despite the fact that natural allopolyploid formation is highly dependent on this phenomenon. We examined the genetic basis for the spontaneous genome doubling of triploid F1 hybrids between the direct ancestors of allohexaploid common wheat (Triticum aestivum L., AABBDD genome), namely Triticumturgidum L. (AABB genome) and Aegilopstauschii Coss. (DD genome). An Ae. tauschii intraspecific lineage that is closely related to the D genome of common wheat was identified by population-based analysis. Two representative accessions, one that produces a high-genome-doubling-frequency hybrid when crossed with a T. turgidum cultivar and the other that produces a low-genome-doubling-frequency hybrid with the same cultivar, were chosen from that lineage for further analyses. A series of investigations including fertility analysis, immunostaining, and quantitative trait locus (QTL) analysis showed that (1) production of functional unreduced gametes through nonreductional meiosis is an early step key to successful hybrid genome doubling, (2) first division restitution is one of the cytological mechanisms that cause meiotic nonreduction during the production of functional male unreduced gametes, and (3) six QTLs in the Ae. tauschii genome, most of which likely regulate nonreductional meiosis and its subsequent gamete production processes, are involved in hybrid genome doubling. Interlineage comparisons of Ae. tauschii’s ability to cause hybrid genome doubling suggested an evolutionary model for the natural variation pattern of the trait in which non-deleterious mutations in six QTLs may have important roles. The findings of this study demonstrated that the

  16. Genetic basis for spontaneous hybrid genome doubling during allopolyploid speciation of common wheat shown by natural variation analyses of the paternal species.

    Directory of Open Access Journals (Sweden)

    Yoshihiro Matsuoka

    Full Text Available The complex process of allopolyploid speciation includes various mechanisms ranging from species crosses and hybrid genome doubling to genome alterations and the establishment of new allopolyploids as persisting natural entities. Currently, little is known about the genetic mechanisms that underlie hybrid genome doubling, despite the fact that natural allopolyploid formation is highly dependent on this phenomenon. We examined the genetic basis for the spontaneous genome doubling of triploid F1 hybrids between the direct ancestors of allohexaploid common wheat (Triticum aestivum L., AABBDD genome, namely Triticumturgidum L. (AABB genome and Aegilopstauschii Coss. (DD genome. An Ae. tauschii intraspecific lineage that is closely related to the D genome of common wheat was identified by population-based analysis. Two representative accessions, one that produces a high-genome-doubling-frequency hybrid when crossed with a T. turgidum cultivar and the other that produces a low-genome-doubling-frequency hybrid with the same cultivar, were chosen from that lineage for further analyses. A series of investigations including fertility analysis, immunostaining, and quantitative trait locus (QTL analysis showed that (1 production of functional unreduced gametes through nonreductional meiosis is an early step key to successful hybrid genome doubling, (2 first division restitution is one of the cytological mechanisms that cause meiotic nonreduction during the production of functional male unreduced gametes, and (3 six QTLs in the Ae. tauschii genome, most of which likely regulate nonreductional meiosis and its subsequent gamete production processes, are involved in hybrid genome doubling. Interlineage comparisons of Ae. tauschii's ability to cause hybrid genome doubling suggested an evolutionary model for the natural variation pattern of the trait in which non-deleterious mutations in six QTLs may have important roles. The findings of this study demonstrated

  17. Natural products research in latin america.

    Science.gov (United States)

    Gupta, M P

    2001-01-01

    The biodiversity found in Latin America is one of the richest in the world, yet its potential as a source of new pharmaceuticals has not been fully investigated. This paper will explore the present status of natural products research in 19 Latin American countries. Future research needs will be presented along with reports on the ethnobotanical and bioprospection projects under way in Latin America. The presentation will be based on data collected over the last five years and will be presented within the framework of the Fine Pharmaceutical Subprogram of the Iberoamerican Program of Science and Technology for Development (CYTED), a novel international cooperation program.

  18. The Rakicidin Family of Anticancer Natural Products

    DEFF Research Database (Denmark)

    Tsakos, Michail; Jacobsen, Kristian Mark; Yu, Wanwan

    2016-01-01

    Rakicidin A is a prominent member of a small class of macrocyclic lipodepsipeptide natural products that contain an electrophilic 4- amido-2,4-pentadienoate (APD) functionality. Rakicidin A displays selective growth inhibitory activity against hypoxic cancer cells as well as imatinib......-resistant chronic myelogenous leukemia (CML) cells. In this paper we present and discuss the two known synthetic routes to rakicidin A, which provide an instructive comparison of strategies used to address the synthetic challenges inherent to rakicidin A. In addition to the synthetic discussion we provide a status...

  19. Metabolomics and dereplication strategies in natural products.

    Science.gov (United States)

    Tawfike, Ahmed Fares; Viegelmann, Christina; Edrada-Ebel, Ruangelie

    2013-01-01

    Metabolomic methods can be utilized to screen diverse biological sources of potentially novel and sustainable sources of antibiotics and pharmacologically-active drugs. Dereplication studies by high resolution Fourier transform mass spectrometry coupled to liquid chromatography (LC-HRFTMS) and nuclear magnetic resonance (NMR) spectroscopy can establish the chemical profile of endophytic and/or endozoic microbial extracts and their plant or animal sources. Identifying the compounds of interest at an early stage will aid in the isolation of the bioactive components. Therefore metabolite profiling is important for functional genomics and in the search for new pharmacologically active compounds. Using the tools of metabolomics through the employment of LC-HRFTMS as well as high resolution NMR will be a very efficient approach. Metabolomic profiling has found its application in screening extracts of macroorganisms as well as in the isolation and cultivation of suspected microbial producers of bioactive natural products.Metabolomics is being applied to identify and biotechnologically optimize the production of pharmacologically active secondary metabolites. The links between metabolome evolution during optimization and processing factors can be identified through metabolomics. Information obtained from a metabolomics dataset can efficiently establish cultivation and production processes at a small scale which will be finally scaled up to a fermenter system, while maintaining or enhancing synthesis of the desired compounds. MZmine (BMC Bioinformatics 11:395-399, 2010; http://mzmine.sourceforge.net/download.shtml ) and SIEVE ( http://www.vastscientific.com/resources/index.html ; Rapid Commun Mass Spectrom 22:1912-1918, 2008) softwares are utilized to perform differential analysis of sample populations to find significant expressed features of complex biomarkers between parameter variables. Metabolomes are identified with the aid of existing high resolution MS and NMR

  20. The chemistry of isoindole natural products

    Directory of Open Access Journals (Sweden)

    Klaus Speck

    2013-10-01

    Full Text Available This review highlights the chemical and biological aspects of natural products containing an oxidized or reduced isoindole skeleton. This motif is found in its intact or modified form in indolocarbazoles, macrocyclic polyketides (cytochalasan alkaloids, the aporhoeadane alkaloids, meroterpenoids from Stachybotrys species and anthraquinone-type alkaloids. Concerning their biological activity, molecular structure and synthesis, we have limited this review to the most inspiring examples. Within different congeners, we have selected a few members and discussed the synthetic routes in more detail. The putative biosynthetic pathways of the presented isoindole alkaloids are described as well.

  1. Natural products from microbes associated with insects

    Directory of Open Access Journals (Sweden)

    Christine Beemelmanns

    2016-02-01

    Full Text Available Here we review discoveries of secondary metabolites from microbes associated with insects. We mainly focus on natural products, where the ecological role has been at least partially elucidated, and/or the pharmaceutical properties evaluated, and on compounds with unique structural features. We demonstrate that the exploration of specific microbial–host interactions, in combination with multidisciplinary dereplication processes, has emerged as a successful strategy to identify novel chemical entities and to shed light on the ecology and evolution of defensive associations.

  2. Natural product-inspired rational design, synthesis and biological evaluation of 2,3-dihydropyrano[2,3-f]chromen-4(8H)-one based hybrids as potential mitochondrial apoptosis inducers.

    Science.gov (United States)

    Sakthivel, Palaniappan; Ilangovan, Andivelu; Kaushik, Mahabir Prasad

    2016-10-21

    Synthesis of novel pyranochromanone amide hybrids, by combining pyranochromanone pharmacophore and privileged scaffolds such as 2-amino-1,3,4-thiadiaole/2-aminothiazole/aminopyridine/aminonaphthalene and anti-cancer evaluation of a series led us to discover a series of new chemical entities (NCEs) showing broad spectrum of anti-cancer activity against three different human cancer cell lines (MCF-7, A549 and HeLa), at IC50 values ranging from 14.3 to 97.8 μM. Among them, some compounds such as 15b, 15d, 20a and 20b displayed excellent activity against breast cancer cell line MCF-7. Detailed biological studies such as AO/EB dual staining, Hoechst 33342 staining, FACS analysis of mitochondrial membrane potential (Δψm) using JC-1 dye and DNA fragmentation confirmed the apoptosis induced by the hybrids. Gene expression studies by Real time RT-PCR has shown that these compounds are efficient regulator of anti-apoptotic gene Bcl-2. Western blot analysis also revealed that these compounds persuade apoptosis through intrinsic pathway by up-regulating the pro-apoptotic protein Bax and down-regulating the anti-apoptotic protein Bcl-2. Molecular docking studies reveal that compounds 15b and 20b binds efficiently with Bcl-2 promoter G-quadruplex.

  3. Multi-site production planning in hybrid make-to-stock/make-to-order production environment

    Science.gov (United States)

    Rafiei, Hamed; Rabbani, Masoud; Kokabi, Reza

    2014-06-01

    Today competitive environment has enforced practitioners and researchers to pay great attention to issues enhancing both production and marketing competitiveness. To do so, it has been obligatory for the firms to consider production side activities while customer requirements are on the other side of competition. In this regard, hybrid make-to-stock (MTS)/make-to-order (MTO) production systems have revealed outstanding results. This paper addresses multi-site production planning of a hybrid manufacturing firm for the first time in the hybrid systems' body of literature. In this regard, a network of suppliers, manufacturers and customers is considered for which a mixed-integer mathematical model is proposed. Objective function of the proposed mathematical model seeks to maximize profitability of the manufacturing firm. Because of computational complexity of the developed mathematical model, a genetic algorithm is developed upon which numerical experiments are reported in order to show validity and applicability of the proposed model.

  4. Natural Products: Insights into Leishmaniasis Inflammatory Response

    Science.gov (United States)

    Rodrigues, Igor A.; Mazotto, Ana Maria; Cardoso, Verônica; Alves, Renan L.; Amaral, Ana Claudia F.; Silva, Jefferson Rocha de Andrade; Pinheiro, Anderson S.; Vermelho, Alane B.

    2015-01-01

    Leishmaniasis is a vector-borne disease that affects several populations worldwide, against which there are no vaccines available and the chemotherapy is highly toxic. Depending on the species causing the infection, the disease is characterized by commitment of tissues, including the skin, mucous membranes, and internal organs. Despite the relevance of host inflammatory mediators on parasite burden control, Leishmania and host immune cells interaction may generate an exacerbated proinflammatory response that plays an important role in the development of leishmaniasis clinical manifestations. Plant-derived natural products have been recognized as bioactive agents with several properties, including anti-protozoal and anti-inflammatory activities. The present review focuses on the antileishmanial activity of plant-derived natural products that are able to modulate the inflammatory response in vitro and in vivo. The capability of crude extracts and some isolated substances in promoting an anti-inflammatory response during Leishmania infection may be used as part of an effective strategy to fight the disease. PMID:26538837

  5. Near infrared spectroscopy in natural products analysis.

    Science.gov (United States)

    Cozzolino, Daniel

    2009-06-01

    Several medicinal and herbal plants properties are related to individual compounds such as essential oils, terpenoids, flavonoids, which are present in natural products in low concentrations (e. g., ppm or ppb). For many years, the use of classical separation and chromatographic and spectrometric techniques such as high performance liquid chromatography (HPLC), gas chromatography (GC), liquid chromatography (LC) and mass spectrometry (MS) were initially used for the elucidation of isolated compounds from different plant matrices. Spectroscopic techniques in the infrared (IR) wavelength region of the electromagnetic spectrum have been used in the food industry to monitor and evaluate the composition of foods. Although Herschel discovered light in the near-infrared (NIR) region as early as 1800, most spectroscopists of the first half of the last century ignored it, in the belief that it lacked any analytical interest. However, during the last 40 years NIR spectroscopy has become one of the most attractive and used methods for analysis. This mini-review highlights recent applications of NIR spectroscopy to the qualitative and quantitative analysis of plant natural products.

  6. Experimental and theoretical assessment of flexural properties of hybrid natural fibre composites

    DEFF Research Database (Denmark)

    Raghavalu Thirumalai, Durai Prabhakaran; Toftegaard, Helmuth Langmaack; Markussen, Christen Malte

    2014-01-01

    The concept of hybridization of natural fibre composites with synthetic fibres is attracting increasing scientific attention. The present study addresses the flexural properties of hybrid flax/glass/epoxy composites to demonstrate the potential benefits of hybridization. The study covers both...... experimental and theoretical assessments. Composite laminates with different hybrid fibre mixing ratios and different layer configurations were manufactured, and their volumetric composition and flexural properties were measured. The relationship between volume fractions in the composites is shown to be well...... predicted as a function of the hybrid fibre mixing ratio. The flexural modulus of the composites is theoretically assessed by using micromechanical models and laminate theory. The model predictions are compared with the experimentally determined flexural properties. Both approaches show that the flexural...

  7. Plant cell culture strategies for the production of natural products.

    Science.gov (United States)

    Ochoa-Villarreal, Marisol; Howat, Susan; Hong, SunMi; Jang, Mi Ok; Jin, Young-Woo; Lee, Eun-Kyong; Loake, Gary J

    2016-03-01

    Plants have evolved a vast chemical cornucopia to support their sessile lifestyles. Man has exploited this natural resource since Neolithic times and currently plant-derived chemicals are exploited for a myriad of applications. However, plant sources of most high-value natural products (NPs) are not domesticated and therefore their production cannot be undertaken on an agricultural scale. Further, these plant species are often slow growing, their populations limiting, the concentration of the target molecule highly variable and routinely present at extremely low concentrations. Plant cell and organ culture constitutes a sustainable, controllable and environmentally friendly tool for the industrial production of plant NPs. Further, advances in cell line selection, biotransformation, product secretion, cell permeabilisation, extraction and scale-up, among others, are driving increases in plant NP yields. However, there remain significant obstacles to the commercial synthesis of high-value chemicals from these sources. The relatively recent isolation, culturing and characterisation of cambial meristematic cells (CMCs), provides an emerging platform to circumvent many of these potential difficulties. [BMB Reports 2016; 49(3): 149-158].

  8. Hybrid transvaginal natural orifice transluminal endoscopic surgery-kolecystektomi

    DEFF Research Database (Denmark)

    Boesen, Line; Meisner, Søren; Vilmann, Peter

    2016-01-01

    Natural orifice transluminal endoscopic surgery (NOTES) is a minimally invasive surgical technique where access to the abdominal cavity is achieved through one of the natural orifices of the body. Based on experience from gynaecology, transvaginal access has been the easiest NOTES technique...

  9. Yoghurt enrichment with natural bee farming products

    Directory of Open Access Journals (Sweden)

    N. Lomova

    2015-05-01

    Full Text Available Introduction. Bee pollen is a unique and unparalleled natural bioactive substances source. Using it in conjunction with the popular functional fermented milk product -yogurt will expand its product range and increase the biological value. Materials and Methods. Dried bee pollen’s moisture determination was made by gravimetry methods, based on the sample weight loss due to desiccation, until constant weight was reached.Test and control yogurt samples were studied by applying standard techniques for milk and milk products set forth in the regulations of Ukraine. Results and discussion. It is found that bee pollen pellet drying to a moisture content of 2 -4%, increases the flow rate of powder almost by 90%. The sample having moisture content of 2% will have a bulk density exceeding 12.5% compared to the sample having moisture content of 10%. Raw output will also increase by 3.7%. By contrast, apparent density and weight fraction of losses decreases, which has a positive impact on pollen efficiency of use and distribution in bulk yogurt. Moreover, the weight fraction of losses decreases by fourfold (4.6% vs. 1%. It was experimentally determined that pollen can deteriorate microbiological characteristics of yogurt. It was proved that treatment of crushed bee pollen pellet sample with ultraviolet allows improving yogurt microbiological safety indicators. Namely, to reduce the presence of coli-forms to 0, mould –to 10 CFU/cm³. Conclusions. The proposed bee pollen pellet treatment method will improve the technological and microbiological characteristics of pollen powder. This provides for yoghurt production biotechnology using bee farming products.

  10. Natural hybridization in heliconiine butterflies: the species boundary as a continuum

    Directory of Open Access Journals (Sweden)

    Beltrán Margarita

    2007-02-01

    Full Text Available Abstract Background To understand speciation and the maintenance of taxa as separate entities, we need information about natural hybridization and gene flow among species. Results Interspecific hybrids occur regularly in Heliconius and Eueides (Lepidoptera: Nymphalidae in the wild: 26–29% of the species of Heliconiina are involved, depending on species concept employed. Hybridization is, however, rare on a per-individual basis. For one well-studied case of species hybridizing in parapatric contact (Heliconius erato and H. himera, phenotypically detectable hybrids form around 10% of the population, but for species in sympatry hybrids usually form less than 0.05% of individuals. There is a roughly exponential decline with genetic distance in the numbers of natural hybrids in collections, both between and within species, suggesting a simple "exponential failure law" of compatibility as found in some prokaryotes. Conclusion Hybridization between species of Heliconius appears to be a natural phenomenon; there is no evidence that it has been enhanced by recent human habitat disturbance. In some well-studied cases, backcrossing occurs in the field and fertile backcrosses have been verified in insectaries, which indicates that introgression is likely, and recent molecular work shows that alleles at some but not all loci are exchanged between pairs of sympatric, hybridizing species. Molecular clock dating suggests that gene exchange may continue for more than 3 million years after speciation. In addition, one species, H. heurippa, appears to have formed as a result of hybrid speciation. Introgression may often contribute to adaptive evolution as well as sometimes to speciation itself, via hybrid speciation. Geographic races and species that coexist in sympatry therefore form part of a continuum in terms of hybridization rates or probability of gene flow. This finding concurs with the view that processes leading to speciation are continuous, rather than

  11. Natural product synthesis at the interface of chemistry and biology.

    Science.gov (United States)

    Hong, Jiyong

    2014-08-11

    Nature has evolved to produce unique and diverse natural products that possess high target affinity and specificity. Natural products have been the richest sources for novel modulators of biomolecular function. Since the chemical synthesis of urea by Wöhler, organic chemists have been intrigued by natural products, leading to the evolution of the field of natural product synthesis over the past two centuries. Natural product synthesis has enabled natural products to play an essential role in drug discovery and chemical biology. With the introduction of novel, innovative concepts and strategies for synthetic efficiency, natural product synthesis in the 21st century is well poised to address the challenges and complexities faced by natural product chemistry and will remain essential to progress in biomedical sciences.

  12. Antibacterial natural products in medicinal chemistry--exodus or revival?

    Science.gov (United States)

    von Nussbaum, Franz; Brands, Michael; Hinzen, Berthold; Weigand, Stefan; Häbich, Dieter

    2006-08-04

    To create a drug, nature's blueprints often have to be improved through semisynthesis or total synthesis (chemical postevolution). Selected contributions from industrial and academic groups highlight the arduous but rewarding path from natural products to drugs. Principle modification types for natural products are discussed herein, such as decoration, substitution, and degradation. The biological, chemical, and socioeconomic environments of antibacterial research are dealt with in context. Natural products, many from soil organisms, have provided the majority of lead structures for marketed anti-infectives. Surprisingly, numerous "old" classes of antibacterial natural products have never been intensively explored by medicinal chemists. Nevertheless, research on antibacterial natural products is flagging. Apparently, the "old fashioned" natural products no longer fit into modern drug discovery. The handling of natural products is cumbersome, requiring nonstandardized workflows and extended timelines. Revisiting natural products with modern chemistry and target-finding tools from biology (reversed genomics) is one option for their revival.

  13. Effect of natural fibers and bio-resins on mechanical properties in hybrid and non-hybrid composites

    Science.gov (United States)

    Fragassa, Cristiano

    2016-05-01

    The aim of the present experimental investigation was to perform a comparative analysis concerning the influence on mechanical properties of natural fibers and/or bio-resins in reinforced thermoset composites. Flax and basalt fibers were selected as natural reinforcements, as single constituents or in hybrid combination. Glass synthetic fibers were used for comparison. Eco-friendly matrixes, both epoxy or vinylester, were considered and compared with composites based on traditional resins. Samples were fabricated by hand lay-up and resin infusion techniques. Cures were accelerated and controlled by applying heat and pressure in autoclave. Tensile, flexural and impact tests were carried out according to ASTM standards.

  14. Production of hybrids between western gray wolves and western coyotes.

    Directory of Open Access Journals (Sweden)

    L David Mech

    Full Text Available Using artificial insemination we attempted to produce hybrids between captive, male, western, gray wolves (Canis lupus and female, western coyotes (Canis latrans to determine whether their gametes would be compatible and the coyotes could produce and nurture offspring. The results contribute new information to an ongoing controversy over whether the eastern wolf (Canis lycaon is a valid unique species that could be subject to the U. S. Endangered Species Act. Attempts with transcervically deposited wolf semen into nine coyotes over two breeding seasons yielded three coyote pregnancies. One coyote ate her pups, another produced a resorbed fetus and a dead fetus by C-section, and the third produced seven hybrids, six of which survived. These results show that, although it might be unlikely for male western wolves to successfully produce offspring with female western coyotes under natural conditions, western-gray-wolf sperm are compatible with western-coyote ova and that at least one coyote could produce and nurture hybrid offspring. This finding in turn demonstrates that gamete incompatibility would not have prevented western, gray wolves from inseminating western coyotes and thus producing hybrids with coyote mtDNA, a claim that counters the view that the eastern wolf is a separate species. However, some of the difficulties experienced by the other inseminated coyotes tend to temper that finding and suggest that more experimentation is needed, including determining the behavioral and physical compatibility of western gray wolves copulating with western coyotes. Thus although our study adds new information to the controversy, it does not settle it. Further study is needed to determine whether the putative Canis lycaon is indeed a unique species.

  15. Production of hybrids between western gray wolves and western coyotes.

    Science.gov (United States)

    Mech, L David; Christensen, Bruce W; Asa, Cheryl S; Callahan, Margaret; Young, Julie K

    2014-01-01

    Using artificial insemination we attempted to produce hybrids between captive, male, western, gray wolves (Canis lupus) and female, western coyotes (Canis latrans) to determine whether their gametes would be compatible and the coyotes could produce and nurture offspring. The results contribute new information to an ongoing controversy over whether the eastern wolf (Canis lycaon) is a valid unique species that could be subject to the U. S. Endangered Species Act. Attempts with transcervically deposited wolf semen into nine coyotes over two breeding seasons yielded three coyote pregnancies. One coyote ate her pups, another produced a resorbed fetus and a dead fetus by C-section, and the third produced seven hybrids, six of which survived. These results show that, although it might be unlikely for male western wolves to successfully produce offspring with female western coyotes under natural conditions, western-gray-wolf sperm are compatible with western-coyote ova and that at least one coyote could produce and nurture hybrid offspring. This finding in turn demonstrates that gamete incompatibility would not have prevented western, gray wolves from inseminating western coyotes and thus producing hybrids with coyote mtDNA, a claim that counters the view that the eastern wolf is a separate species. However, some of the difficulties experienced by the other inseminated coyotes tend to temper that finding and suggest that more experimentation is needed, including determining the behavioral and physical compatibility of western gray wolves copulating with western coyotes. Thus although our study adds new information to the controversy, it does not settle it. Further study is needed to determine whether the putative Canis lycaon is indeed a unique species.

  16. Production of hybrids between western gray wolves and western coyotes

    Science.gov (United States)

    Mech, L. David; Christensen, Bruce W.; Asa, Cheryl S.; Callahan, Magaret; Young, Julie K.

    2014-01-01

    Using artificial insemination we attempted to produce hybrids between captive, male, western, gray wolves (Canis lupus) and female, western coyotes (Canis latrans) to determine whether their gametes would be compatible and the coyotes could produce and nurture offspring. The results contribute new information to an ongoing controversy over whether the eastern wolf (Canis lycaon) is a valid unique species that could be subject to the U. S. Endangered Species Act. Attempts with transcervically deposited wolf semen into nine coyotes over two breeding seasons yielded three coyote pregnancies. One coyote ate her pups, another produced a resorbed fetus and a dead fetus by C-section, and the third produced seven hybrids, six of which survived. These results show that, although it might be unlikely for male western wolves to successfully produce offspring with female western coyotes under natural conditions, western-gray-wolf sperm are compatible with western-coyote ova and that at least one coyote could produce and nurture hybrid offspring. This finding in turn demonstrates that gamete incompatibility would not have prevented western, gray wolves from inseminating western coyotes and thus producing hybrids with coyote mtDNA, a claim that counters the view that the eastern wolf is a separate species. However, some of the difficulties experienced by the other inseminated coyotes tend to temper that finding and suggest that more experimentation is needed, including determining the behavioral and physical compatibility of western gray wolves copulating with western coyotes. Thus although our study adds new information to the controversy, it does not settle it. Further study is needed to determine whether the putative Canis lycaon is indeed a unique species.

  17. Hybrids between cultivated and wild carrots in natural populations in Denmark

    DEFF Research Database (Denmark)

    Magnussen, L.S.; Hauser, Thure Pavlo

    2007-01-01

    in warmer regions of the world. To test whether hybrids are formed and survive in wild Danish populations, and whether prolonged hybridization has led to introgression of cultivar genes, we collected leaf material from adult individuals growing close to carrot fields and analysed their genotypic composition......Many cultivated plant species are able to hybridize with related wild plants. However, it is not clear whether their hybrids are able to survive and reproduce outside managed fields, and if cultivar genes introgress into wild populations. In areas where wild carrots co-occur with carrot root......-crops, pollen and seeds may flow from two different sources in the fields to the surrounding wild populations: from pure cultivar plants that occasionally flower, and from flowering 'bolters' that originate from hybridizations between wild (male) and cultivated carrots (female) in seed production fields...

  18. The automation of natural product structure elucidation.

    Science.gov (United States)

    Steinbeck, C

    2001-05-01

    The last two or three years have seen exciting developments in the field of computer-assisted structure elucidation (CASE) with a number of programs becoming commercially or freely available. This was the conditio sine qua non for CASE to be widely applied in the daily work of bench chemists and spectroscopists. A number of promising applications have been published in the area of structure generators, deterministic and stochastic CASE tools and property predictions, including the automatic distinction between natural products and artificial compounds, as well as the determination of 3-D structure from a connection table based on IR spectroscopy. Advancements in coupling techniques between chromatographic and spectroscopic methods demonstrate progress towards a fully automated structure elucidation or identification process starting at the earliest steps of obtaining crude extracts.

  19. Chemistry of natural products: A veritable approach to the ...

    African Journals Online (AJOL)

    Chemistry of natural products: A veritable approach to the development of drugs for combating ... PROMOTING ACCESS TO AFRICAN RESEARCH ... The earth's resources, especially natural products, are no doubt important materials from ...

  20. Study of the Productivity and Surface Quality of Hybrid EDM

    Science.gov (United States)

    Wankhade, Sandeepkumar Haribhau; Sharma, Sunil Bansilal

    2016-01-01

    The development of new, advanced engineering materials and the need for precise prototypes and low-volume production have made the electric discharge machining (EDM), an important manufacturing process to meet such demands. It is capable of machining geometrically complex and hard material components, that are precise and difficult-to-machine such as heat treated tool steels, composites, super alloys, ceramics, carbides etc. Conversely the low MRR limits its productivity. Abrasive water jet machine (AJM) tools are quick to setup and offer quick turn-around on the machine and could make parts out of virtually any material. They do not heat the material hence no heat affected zone and can make any intricate shape easily. The main advantages are flexibility, low heat production and ability to machine hard and brittle materials. Main disadvantages comprise the process produces a tapered cut and health hazards due to dry abrasives. To overcome the limitations and exploit the best of each of above processes; an attempt has been made to hybridize the processes of AJM and EDM. The appropriate abrasives routed with compressed air through the hollow electrode to construct the hybrid process i.e., abrasive jet electric discharge machining (AJEDM), the high speed abrasives could impinge on the machined surface to remove the recast layer caused by EDM process. The main process parameters were varied to explore their effects and experimental results show that AJEDM enhances the machining efficiency with better surface finish hence can fit the requirements of modern manufacturing applications.

  1. Development of hybrid genetic algorithms for product line designs.

    Science.gov (United States)

    Balakrishnan, P V Sundar; Gupta, Rakesh; Jacob, Varghese S

    2004-02-01

    In this paper, we investigate the efficacy of artificial intelligence (AI) based meta-heuristic techniques namely genetic algorithms (GAs), for the product line design problem. This work extends previously developed methods for the single product design problem. We conduct a large scale simulation study to determine the effectiveness of such an AI based technique for providing good solutions and bench mark the performance of this against the current dominant approach of beam search (BS). We investigate the potential advantages of pursuing the avenue of developing hybrid models and then implement and study such hybrid models using two very distinct approaches: namely, seeding the initial GA population with the BS solution, and employing the BS solution as part of the GA operator's process. We go on to examine the impact of two alternate string representation formats on the quality of the solutions obtained by the above proposed techniques. We also explicitly investigate a critical managerial factor of attribute importance in terms of its impact on the solutions obtained by the alternate modeling procedures. The alternate techniques are then evaluated, using statistical analysis of variance, on a fairy large number of data sets, as to the quality of the solutions obtained with respect to the state-of-the-art benchmark and in terms of their ability to provide multiple, unique product line options.

  2. Chocolate: A Marvelous Natural Product of Chemistry

    Science.gov (United States)

    Tannenbaum, Ginger

    2004-08-01

    Chocolate is a natural product as ubiquitous as television. Of course, it is eaten, but it is also found in air fresheners, marking pens, flavoring in a multitude of products including soda pop, and as an aroma in "chocolate-dyed" T-shirts. However, most of us are completely unaware of the complex chemical reactions that take place to produce chocolate and the necessary technology that has evolved to produce chocolate and all its byproducts. Processing results in a mixture of many components, an interesting contrast to most of the simple, one-step reactions introduced at the high school level. This article is a survey of chocolate from tree to table. After a brief introduction to the history of chocolate and how and where it is grown, the manufacturing process is examined, and the chemistry is explored. A bit of the jargon used in the industry is mentioned. Cocoa butter is a significant ingredient in chocolate, and an investigation of it introduces triglycerides, fatty acids, polymorphic behavior, and molecular packing of the fats in chocolate and how they affect the tempering process. There is a brief discussion of chocolate's non-Newtonian behavior and the resulting challenges presented in the manufacturing process. See Featured Molecules Featured on the Cover

  3. Thermoplastic impact property improvement in hybrid natural fibre epoxy composite bumper beam

    Energy Technology Data Exchange (ETDEWEB)

    Davoodi, M M; Sapuan, S M; Ali, Aidy [Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia 43400 UPM Serdang, Selangor (Malaysia); Ahmad, D; Khalina, A, E-mail: makinejadm2@asme.org [Department of Biological and Agricultural Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia)

    2010-05-15

    Utilization of thermoset resin as a bumper beam composite matrix is currently more dominated in car manufacturer suppliers, because of availability, easy processing, low material cost and production equipment investment. Moreover, low viscosity, shrinkage and excellent flow facilitate better fibre impregnation and proper surface resin wetting. Three-dimensional cross linking curing increase impact, creep and environmental stress cracking resistance properties. Low impact properties of natural fibre epoxy composite, are main issues in its employment for automotive structural components. Impact properties in epoxy composite bumper beam could be increased by modifying the resin, reinforcement and manufacturing process as well as geometry parameters such as cross section, thickness, added ribs and fixing method optimizations could strengthen impact resistance. There are two main methods, flexibilisation and toughening, as modifying the resin in order to improve the impact properties of epoxy composite, which form single phase or two-phase morphology to make modifier as epoxy or from separate phase to keep the thermo-mechanical properties. Liquid rubber, thermoplastic, core shell particle and rigid particle are different methods of toughening improvements. In this research, thermoplastic toughening has used to improve impact properties in hybrid natural fibre epoxy composite for automotive bumper beam and has achieved reasonable impact improvements.

  4. Thermoplastic impact property improvement in hybrid natural fibre epoxy composite bumper beam

    Science.gov (United States)

    Davoodi, M. M.; Sapuan, S. M.; Ali, Aidy; Ahmad, D.; Khalina, A.

    2010-05-01

    Utilization of thermoset resin as a bumper beam composite matrix is currently more dominated in car manufacturer suppliers, because of availability, easy processing, low material cost and production equipment investment. Moreover, low viscosity, shrinkage and excellent flow facilitate better fibre impregnation and proper surface resin wetting. Three-dimensional cross linking curing increase impact, creep and environmental stress cracking resistance properties. Low impact properties of natural fibre epoxy composite, are main issues in its employment for automotive structural components. Impact properties in epoxy composite bumper beam could be increased by modifying the resin, reinforcement and manufacturing process as well as geometry parameters such as cross section, thickness, added ribs and fixing method optimizations could strengthen impact resistance. There are two main methods, flexibilisation and toughening, as modifying the resin in order to improve the impact properties of epoxy composite, which form single phase or two-phase morphology to make modifier as epoxy or from separate phase to keep the thermo-mechanical properties. Liquid rubber, thermoplastic, core shell particle and rigid particle are different methods of toughening improvements. In this research, thermoplastic toughening has used to improve impact properties in hybrid natural fibre epoxy composite for automotive bumper beam and has achieved reasonable impact improvements.

  5. Natural products--a simple model to explain chemical diversity.

    Science.gov (United States)

    Firn, Richard D; Jones, Clive G

    2003-08-01

    A simple evolutionary model is presented which explains why organisms produce so many natural products, why so many have low biological activity, why enzymes involved in natural product synthesis have the properties they do and why natural product metabolism is shaped as it is.

  6. The nature of interactions that contribute to postzygotic reproductive isolation in hybrid copepods.

    Science.gov (United States)

    Willett, Christopher S

    2011-05-01

    Deleterious interactions within the genome of hybrids can lower fitness and result in postzygotic reproductive isolation. Understanding the genetic basis of these deleterious interactions, known as Dobzhansky-Muller incompatibilities, is the subject of intense current study that seeks to elucidate the nature of these deleterious interactions. Hybrids from crosses of individuals from genetically divergent populations of the intertidal copepod Tigriopus californicus provide a useful model in which to study Dobzhansky-Muller incompatibilities. Studies of the basis of postzygotic reproductive isolation in this species have revealed a number of patterns. First, there is evidence for a breakdown in genomic coadaptation between mtDNA-encoded and nuclear-encoded proteins that can result in a reduction in hybrid fitness in some crosses. It appears from studies of the individual genes involved in these interactions that although this coadaptation could lead to asymmetries between crosses, patterns of genotypic viabilities are not often consistent with simple models of genomic coadaptation. Second, there is a large impact of environmental factors on these deleterious interactions suggesting that they are not strictly intrinsic in nature. Temperature in particular appears to play an important role in determining the nature of these interactions. Finally, deleterious interactions in these hybrid copepods appear to be complex in terms of the number of genetic factors that interact to lead to reductions in hybrid fitness. This complexity may stem from three or more factors that all interact to cause a single incompatibility or the same factor interacting with multiple other factors independently leading to multiple incompatibilities.

  7. [The recent research progress of chemistry of marine natural products].

    Science.gov (United States)

    Shi, Qing-wen; Li, Li-geng; Wang, Yu-fang; Huo, Chang-hong; Zhang, Man-li

    2010-10-01

    Ocean is a unique and excellent resource that provides a diverse array of intriguing natural products. Marine natural products have demonstrated significant and extremely potent biological activities and have captured the attention of natural products chemists in the past few decades. It is increasingly recognized that a wealth of fascinating natural products and novel chemical entities will play a dominant role in the discovery of useful leads for the development of pharmaceutical agents and provide useful probes to lead to breakthroughs in a variety of life-science fields. This article focused on the research progress of chemistry of marine natural products in recent five years.

  8. Sugarcane Aphid Population Growth, Plant Injury, and Natural Enemies on Selected Grain Sorghum Hybrids in Texas and Louisiana.

    Science.gov (United States)

    Brewer, Michael J; Gordy, John W; Kerns, David L; Woolley, James B; Rooney, William L; Bowling, Robert D

    2017-09-06

    In response to the 2013 outbreak of sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), on sorghum, Sorghum bicolor (L.), in North America, experiments were conducted at three southern U.S. grain sorghum production locations (Corpus Christi, TX; Winnsboro, LA; Rosenberg, TX). The objectives were to authenticate yield decline on susceptible hybrids (2014 and 2015) and to measure aphid population growth and natural enemy prevalence on susceptible and resistant hybrids with similar genetic background (2014). Yield decline on susceptible hybrids (Tx 2752/Tx430 and DKS53-67) was more substantial when aphid population growth accelerated quickly and peaked above 300 aphids per leaf (50 to nearly 100% yield decline). Location and year variation in maximum aphid density and cumulative aphid-days was high, with doubling time values on the susceptible hybrids ranging between 3.9 and 7.9 d. On resistant Tx2752/Tx2783, leaf injury and yield decline were not seen or less severe than on its paired susceptible Tx2752/Tx430. Aphids declined on Tx2752/Tx2783 after initial colony establishment (Corpus Christi) or took about 60% longer to double in population size when compared with Tx2572/Tx430 (Winnsboro). The predominant natural enemy taxa were aphelinid mummies (Hymenoptera: Aphelinidae), ladybird beetles (Coleoptera: Coccinellidae), and sryphid flies (Diptera: Syrphidae), and they were more prevalent during flowering than prior to flowering. They were generally responsive to changes in aphid density of both susceptible and resistant hybrids, but variability points to need for further study. In future research, full season observations should continue as well as more detailed study of potential compatibility of sorghum resistance and biological control. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Beware When Buying "All Natural" Erectile Dysfunction Products

    Science.gov (United States)

    ... Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products For Consumers Home For Consumers Protect Yourself Health Fraud Beware When Buying "All Natural" Erectile Dysfunction Products Share Tweet Linkedin Pin it ...

  10. Oxygen-containing fragments in natural products.

    Science.gov (United States)

    Titarenko, Zoya; Vasilevich, Natalya; Zernov, Vladimir; Kirpichenok, Michael; Genis, Dmitry

    2013-02-01

    An analysis of the chemical environment of the oxygen atoms in the DNP database compared to the CMC and SCD databases was performed. Some structural clusters were identified which are predominant among the natural products and can be considered as distinctive features of NPs. Fifty-three oxygen-containing structural fragments that are distinctive for the DNP (distinctive set of fragments DSF) in comparison with the SCD have been identified. A new descriptor Mc was introduced for describing the ratio of atoms involved in the DSF to the total number of heavy atoms. A significant difference in the Mc values among the reference databases allowed the use of a specific cluster of the DSF as a tool for performing similarity searches for oxygen-containing NP molecules, or for evaluation or comparison of databases according to their NP-likeness. An example illustrating that the suggested approach could allow not only estimating the NP-likeness, but also serve as a tool for designing new NP-like compounds is provided. The suggested approach for NP-likeness evaluation moves away from the traditional ideas of scaffolds, cycles, linkers and substituents.

  11. Antifouling Activity of Marine Natural Products

    KAUST Repository

    Qian, Pei-Yuan

    2012-01-01

    With the global ban of application of organotin-based marine coatings by International Maritime Organization in 2008, there is a practical and urgent need of identifying environmentally friendly low-toxic and nontoxic antifouling compounds for marine industries. Marine natural products have been considered as one of the most promising sources of antifouling compounds in recent years. In antifouling compound screening processes, bioassay systems often play most critical/vital roles in screening efforts. To meet various needs, a variety of bioassay systems have been developed and/or adopted in both research and commercial laboratories. In this chapter, we provide a brief outline of common bioassay procedures for both antimicrofouling and antimacrofouling assays, which can serve as a general guideline for setting up bioassay systems in laboratories engaged in antifouling compound screening. Some bioassay procedures currently practiced in various laboratories are not included in this book chapter for various reasons. Individual laboratories should modify bioassay protocols based on their research interests or needs. Nevertheless, we highly recommend the research laboratories to adapt high-throughput assays as much as possible for preliminary screening assays, followed by more complex bioassay processes using multiple target species. We argue strongly for studies in mode-of-action of antifouling compounds against settling propagules, which shall lead to discovery of molecular biomarkers (genes, proteins, receptors, or receptor system) and will allow us to design more targeted bioassay systems.

  12. A Historical Overview of Natural Products in Drug Discovery

    Science.gov (United States)

    Dias, Daniel A.; Urban, Sylvia; Roessner, Ute

    2012-01-01

    Historically, natural products have been used since ancient times and in folklore for the treatment of many diseases and illnesses. Classical natural product chemistry methodologies enabled a vast array of bioactive secondary metabolites from terrestrial and marine sources to be discovered. Many of these natural products have gone on to become current drug candidates. This brief review aims to highlight historically significant bioactive marine and terrestrial natural products, their use in folklore and dereplication techniques to rapidly facilitate their discovery. Furthermore a discussion of how natural product chemistry has resulted in the identification of many drug candidates; the application of advanced hyphenated spectroscopic techniques to aid in their discovery, the future of natural product chemistry and finally adopting metabolomic profiling and dereplication approaches for the comprehensive study of natural product extracts will be discussed. PMID:24957513

  13. Effective use of heterologous hosts for characterization of biosynthetic enzymes allows production of natural products and promotes new natural product discovery.

    Science.gov (United States)

    Watanabe, Kenji

    2014-01-01

    In the past few years, there has been impressive progress in elucidating the mechanism of biosynthesis of various natural products accomplished through the use of genetic, molecular biological and biochemical techniques. Here, we present a comprehensive overview of the current results from our studies on fungal natural product biosynthetic enzymes, including nonribosomal peptide synthetase and polyketide synthase-nonribosomal peptide synthetase hybrid synthetase, as well as auxiliary enzymes, such as methyltransferases and oxygenases. Specifically, biosynthesis of the following compounds is described in detail: (i) Sch210972, potentially involving a Diels-Alder reaction that may be catalyzed by CghA, a functionally unknown protein identified by targeted gene disruption in the wild type fungus; (ii) chaetoglobosin A, formed via multi-step oxidations catalyzed by three redox enzymes, one flavin-containing monooxygenase and two cytochrome P450 oxygenases as characterized by in vivo biotransformation of relevant intermediates in our engineered Saccharomyces cerevisiae; (iii) (-)-ditryptophenaline, formed by a cytochrome P450, revealing the dimerization mechanism for the biosynthesis of diketopiperazine alkaloids; (iv) pseurotins, whose variations in the C- and O-methylations and the degree of oxidation are introduced combinatorially by multiple redox enzymes; and (v) spirotryprostatins, whose spiro-carbon moiety is formed by a flavin-containing monooxygenase or a cytochrome P450 as determined by heterologous de novo production of the biosynthetic intermediates and final products in Aspergillus niger. We close our discussion by summarizing some of the key techniques that have facilitated the discovery of new natural products, production of their analogs and identification of biosynthetic mechanisms in our study.

  14. Comparative Simulation Study of Production Scheduling in the Hybrid and the Parallel Flow

    Directory of Open Access Journals (Sweden)

    Varela Maria L.R.

    2017-06-01

    Full Text Available Scheduling is one of the most important decisions in production control. An approach is proposed for supporting users to solve scheduling problems, by choosing the combination of physical manufacturing system configuration and the material handling system settings. The approach considers two alternative manufacturing scheduling configurations in a two stage product oriented manufacturing system, exploring the hybrid flow shop (HFS and the parallel flow shop (PFS environments. For illustrating the application of the proposed approach an industrial case from the automotive components industry is studied. The main aim of this research to compare results of study of production scheduling in the hybrid and the parallel flow, taking into account the makespan minimization criterion. Thus the HFS and the PFS performance is compared and analyzed, mainly in terms of the makespan, as the transportation times vary. The study shows that the performance HFS is clearly better when the work stations’ processing times are unbalanced, either in nature or as a consequence of the addition of transport times just to one of the work station processing time but loses advantage, becoming worse than the performance of the PFS configuration when the work stations’ processing times are balanced, either in nature or as a consequence of the addition of transport times added on the work stations’ processing times. This means that physical layout configurations along with the way transport time are including the work stations’ processing times should be carefully taken into consideration due to its influence on the performance reached by both HFS and PFS configurations.

  15. Influence of nanoclay-carbon black hybrid fillers on cure and properties of natural rubber compounds

    NARCIS (Netherlands)

    Sapkota, J.; Poikelispää, M.; Das, A.; Dierkes, W.K.; Vuorinen, J.

    2013-01-01

    The influence of organically modified nanoclay-carbon black (CB) hybrid filler on the curing behavior of natural rubber (NR) was explored in this investigation. Here an effort was paid to understand the curing kinetics of organomodified nanoclay filled rubber compounds. On the basis of two different

  16. Hybrid Polymer/UiO-66(Zr) and Polymer/NaY Fiber Sorbents for Mercaptan Removal from Natural Gas.

    Science.gov (United States)

    Chen, Grace; Koros, William J; Jones, Christopher W

    2016-04-20

    Zeolite NaY and metal organic frameworks MIL-53(Al) and UiO-66(Zr) are spun with cellulose acetate (CA) polymer to create hybrid porous composite fibers for the selective adsorption of sulfur odorant compounds from pipeline natural gas. Odorant removal is desirable to limit corrosion associated with sulfur oxide production, thereby increasing lifetime in gas turbines used for electricity generation. In line with these goals, the performance of the hybrid fibers is evaluated on the basis of sulfur sorption capacity and selectivity, as well as fiber stability and regenerability, compared to their polymer-free sorbent counterparts. The capacities of the powder sorbents are also measured using various desorption temperatures to evaluate the potential for lower temperature, energy, and cost-efficient system operation. Both NaY/CA and UiO-66(Zr)/CA hybrid fibers are prepared with high sorbent loadings, and both have high capacities and selectivities for t-butyl mercaptan (TBM) odorant sorption from a model natural gas (NG), while being stable to multiple regeneration cycles. The different advantages and disadvantages of both types of fibers relative are discussed, with both offering the potential advantages of low pressure drop, rapid heat and mass transfer, and low energy requirements over traditional sulfur removal technologies such as hydrodesulfurization (HDS) or adsorption in a pellet packed beds.

  17. The genetic architecture of reproductive isolation in Louisiana irises: hybrid fitness in nature.

    Science.gov (United States)

    Taylor, Sunni J; Arnold, Michael; Martin, Noland H

    2009-10-01

    Negative epistasis in hybrid genomes commonly results in postzygotic isolation between divergent lineages. However, some genomic regions may be selectively neutral or adaptive in hybrids and thus may potentially cross species barriers. We examined postzygotic isolation between ecologically similar species of Louisiana Iris: Iris brevicaulis and I. fulva to determine the potential for adaptive introgression in nature. Line-cross analyses allowed us a general overview of the gene action responsible for fitness-related traits. We then used a QTL mapping approach to detect genomic regions responsible for variation in these traits. Although hybrid classes suffered reduced fitness for many traits, hybrid means were equivalent to at least one of the parental species in overall estimates of maternal and paternal fitness during the two years of the field study. The genetic architecture underlying the fitness-related traits varied across field site and year of the study, thus emphasizing the importance of the environment in determining the degree of postzygotic isolation and potential for introgression across natural hybrid zones.

  18. Enological characterization of natural hybrids from Saccharomyces cerevisiae and S. kudriavzevii.

    Science.gov (United States)

    González, Sara S; Gallo, Luisa; Climent, M A Dolores; Barrio, Eladio; Querol, Amparo

    2007-05-01

    The effect of yeasts on wine flavor response is of primary importance. The genus Saccharomyces, and mainly the species Saccharomyces cerevisiae, is responsible for alcoholic fermentation. Recently, several novel yeast isolates from wines have been described as hybrid yeasts between S. cerevisiae x S. kudriavzevii. We have analyzed their influence on two grape musts (Macabeo and Tempranillo) in fermentations conducted at four different temperatures (14, 18, 22 and 32 degrees C) by studying volatile compound production, sugar assimilation and other characteristics influencing the enological properties of wine caused by the impact of yeast. Hybrid yeasts behave particularly well at 14, 18 and 22 degrees C and the commercial strain of S. cerevisiae (T73) is better adapted at higher temperatures. Regarding the production of glycerol, acetic acid and malic acid, the hybrids display moderate behavior and concerning aromatic compound production, they are greater producers of higher alcohols. The behavior displayed by these hybrids in the fermentations studied in this work leads us to conclude that the use of hybrid strains can constitute an advantage in wine making.

  19. Pharmaceuticals from natural products: current trends

    Directory of Open Access Journals (Sweden)

    PETER R. SEIDL

    2002-03-01

    Full Text Available The use of products extracted from plants for medicinal purposes can be traced to the beginnings of civilization and up until the end of the nineteenth century natural products were the principal source of medicines. Since then their relative importance has oscillated according to the strategies of large pharmaceutical companies. Now that these strategies are changing, there are new opportunities for countries like Brazil, in which a large proportion of the world's biodiversity is located. There are, however, new circumstances that must be taken into consideration: material must be collected by groups which are formally authorized to do so and under the conditions of the Convention of Biological Diversity, the discovery process is being successively outsourced to smaller specialized firms and there is a growing integration with producers of cosmetics and phytomedicines.O uso de produtos extraídos de plantas para fins medicinais pode ser tracejado aos inícios da civilização e até o fim do século XIX, os produtos naturais constituíram a principal fonte de medicamentos. Desde então, a importância relativa dos produtos naturais tem oscilado de acordo com as estratégias de grandes companhias farmacêuticas. Agora que estas estratégias vêm mudando, há novas oportunidades para países como o Brasil, no qual está localizada uma vasta proporção da biodiversidade mundial. Há, entretanto, novas circunstâncias que devem ser levadas em consideração: o material deve ser coletado por grupos que estão formalmente autorizados para tal, com a coleta sendo feita sob as condições da Convenção de Diversidade Biológica, o processo de descoberta está sendo sucessivamente terceirizado no sentido de firmas especializadas menores e há uma integração crescente como produtores de cosméticos e fitomedicamentos.

  20. Natural product proteomining, a quantitative proteomics platform, allows rapid discovery of biosynthetic gene clusters for different classes of natural products.

    Science.gov (United States)

    Gubbens, Jacob; Zhu, Hua; Girard, Geneviève; Song, Lijiang; Florea, Bogdan I; Aston, Philip; Ichinose, Koji; Filippov, Dmitri V; Choi, Young H; Overkleeft, Herman S; Challis, Gregory L; van Wezel, Gilles P

    2014-06-19

    Information on gene clusters for natural product biosynthesis is accumulating rapidly because of the current boom of available genome sequencing data. However, linking a natural product to a specific gene cluster remains challenging. Here, we present a widely applicable strategy for the identification of gene clusters for specific natural products, which we name natural product proteomining. The method is based on using fluctuating growth conditions that ensure differential biosynthesis of the bioactivity of interest. Subsequent combination of metabolomics and quantitative proteomics establishes correlations between abundance of natural products and concomitant changes in the protein pool, which allows identification of the relevant biosynthetic gene cluster. We used this approach to elucidate gene clusters for different natural products in Bacillus and Streptomyces, including a novel juglomycin-type antibiotic. Natural product proteomining does not require prior knowledge of the gene cluster or secondary metabolite and therefore represents a general strategy for identification of all types of gene clusters.

  1. Capital productivity and the nature of competition

    OpenAIRE

    Börsch-Supan, Axel

    1997-01-01

    This paper measures capital productivity in West Germany, Japan and the United States and links capital productivity to financial performance. We show that West Germany and Japan have significantly lower levels of capital productivity than the United States, mainly due to lower capital utilization but also because less productive capacity was created per unit of physical assets. On a higher level of causality, we show that this mainly comes from less pressure from product market competition a...

  2. Role of natural product diversity in chemical biology.

    Science.gov (United States)

    Hong, Jiyong

    2011-06-01

    Through the natural selection process, natural products possess a unique and vast chemical diversity and have been evolved for optimal interactions with biological macromolecules. Owing to their diversity, target affinity, and specificity, natural products have demonstrated enormous potential as modulators of biomolecular function, been an essential source for drug discovery, and provided design principles for combinatorial library development.

  3. Natural Product Biosynthetic Diversity and Comparative Genomics of the Cyanobacteria.

    Science.gov (United States)

    Dittmann, Elke; Gugger, Muriel; Sivonen, Kaarina; Fewer, David P

    2015-10-01

    Cyanobacteria are an ancient lineage of slow-growing photosynthetic bacteria and a prolific source of natural products with intricate chemical structures and potent biological activities. The bulk of these natural products are known from just a handful of genera. Recent efforts have elucidated the mechanisms underpinning the biosynthesis of a diverse array of natural products from cyanobacteria. Many of the biosynthetic mechanisms are unique to cyanobacteria or rarely described from other organisms. Advances in genome sequence technology have precipitated a deluge of genome sequences for cyanobacteria. This makes it possible to link known natural products to biosynthetic gene clusters but also accelerates the discovery of new natural products through genome mining. These studies demonstrate that cyanobacteria encode a huge variety of cryptic gene clusters for the production of natural products, and the known chemical diversity is likely to be just a fraction of the true biosynthetic capabilities of this fascinating and ancient group of organisms.

  4. Industrial natural product chemistry for drug discovery and development.

    Science.gov (United States)

    Bauer, Armin; Brönstrup, Mark

    2014-01-01

    Covering: up to March 2013. In addition to their prominent role in basic biological and chemical research, natural products are a rich source of commercial products for the pharmaceutical and other industries. Industrial natural product chemistry is of fundamental importance for successful product development, as the vast majority (ca. 80%) of commercial drugs derived from natural products require synthetic efforts, either to enable economical access to bulk material, and/or to optimize drug properties through structural modifications. This review aims to illustrate issues on the pathway from lead to product, and how they have been successfully addressed by modern natural product chemistry. It is focused on natural products of current relevance that are, or are intended to be, used as pharmaceuticals.

  5. Molecular Evidence for Natural Hybridization between Cotoneaster dielsianus and C. glaucophyllus

    Directory of Open Access Journals (Sweden)

    Mingwan Li

    2017-05-01

    Full Text Available Hybridization accompanied by polyploidization and apomixis has been demonstrated as a driving force in the evolution and speciation of many plants. A good example to study the evolutionary process of hybridization associated with polyploidy and apomixis is the genus Cotoneaster (Rosaceae, which includes approximately 150 species, most of which are polyploid apomicts. In this study, we investigated all Cotoneaster taxa distributed in a small region of Malipo, Yunnan, China. Based on the morphological characteristics, four Cotoneaster taxa were identified and sampled: C. dielsianus, C. glaucophyllus, C. franchetii, and a putative hybrid. Flow cytometry analyses showed that C. glaucophyllus was diploid, while the other three taxa were tetraploid. A total of five low-copy nuclear genes and six chloroplast regions were sequenced to validate the status of the putative hybrid. Sequence analyses showed that C. dielsianus and C. glaucophyllus are distantly related and they could be well separated using totally 50 fixed nucleotide substitutions and four fixed indels at the 11 investigated genes. All individuals of the putative hybrid harbored identical sequences: they showed chromatogram additivity for all fixed differences between C. dielsianus and C. glaucophyllus at the five nuclear genes, and were identical with C. glaucophyllus at the six chloroplast regions. Haplotype analysis revealed that C. dielsianus possessed nine haplotypes for the 11 genes, while C. glaucophyllus had ten, and there were no shared haplotypes between the two species. The putative hybrid harbored two haplotypes for each nuclear gene: one shared with C. dielsianus and the other with C. glaucophyllus. They possessed the same chloroplast haplotype with C. glaucophyllus. Our study provided convincing evidence for natural hybridization between C. dielsianus and C. glaucophyllus, and revealed that all hybrid individuals were derivatives of one initial F1 via apomixes. C. glaucophyllus

  6. Copy, edit, and paste: natural product approaches to biomaterials and neuroengineering.

    Science.gov (United States)

    Gademann, Karl

    2015-03-17

    of the synthesis. Along these lines, we have demonstrated that militarinone D can be truncated to yield structurally simplified analogs with improved activity. Finally, with the goal of designing bioactive materials, we have immobilized functionally optimized, neuritogenic natural products ("paste"). These materials could facilitate nerve regeneration, act as nerve guidance conduits, or lead to new approaches in neuroengineering. Based on the surface-adhesive properties of electron-deficient catecholates and the knowledge gathered on neuritogenic natural product derivatives, two mechanistically different design principles have been applied to generate neuritogenic materials. In conclusion, natural products, and their functionally optimized analogs, present a large, mostly untapped reservoir of powerful modulators of biological systems, and their hybridization with materials can lead to new approaches in various fields, from biofilm prevention to neuroengineering.

  7. Biosynthesis of therapeutic natural products using synthetic biology.

    Science.gov (United States)

    Awan, Ali R; Shaw, William M; Ellis, Tom

    2016-10-01

    Natural products are a group of bioactive structurally diverse chemicals produced by microorganisms and plants. These molecules and their derivatives have contributed to over a third of the therapeutic drugs produced in the last century. However, over the last few decades traditional drug discovery pipelines from natural products have become far less productive and far more expensive. One recent development with promise to combat this trend is the application of synthetic biology to therapeutic natural product biosynthesis. Synthetic biology is a young discipline with roots in systems biology, genetic engineering, and metabolic engineering. In this review, we discuss the use of synthetic biology to engineer improved yields of existing therapeutic natural products. We further describe the use of synthetic biology to combine and express natural product biosynthetic genes in unprecedented ways, and how this holds promise for opening up completely new avenues for drug discovery and production. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Natural health products and cancer chemotherapy and radiation therapy

    Directory of Open Access Journals (Sweden)

    Doreen Oneschuk

    2011-12-01

    Full Text Available Complementary therapies, notably natural health products such as herbs and vitamins, are frequently used by cancer patients receiving chemotherapy and radiation therapy. There is much controversy as to whether these natural health products should be taken during conventional cancer treatments. Supporters of this practice cite beneficial effects of the antioxidant properties, while opponents are concerned about the potential for natural health product-chemotherapy/radiation related negative interactions. This involves understanding the role and effect on metabolizing enzymes. This review will highlight the present evidence for both the beneficial and negative consequences of the use of natural health products during chemotherapy and radiation therapy.

  9. The Complexity of Monotone Hybrid Logics over Linear Frames and the Natural Numbers

    CERN Document Server

    Göller, Stefan; Mundhenk, Martin; Schneider, Thomas; Thomas, Michael; Weiss, Felix

    2012-01-01

    Hybrid logic with binders is an expressive specification language. Its satisfiability problem is undecidable in general. If frames are restricted to the natural numbers or general linear orders, then satisfiability is known to be decidable, but of non-elementary complexity. In this paper, we consider monotone hybrid logics (i.e., the Boolean connectives are conjunction and disjunction only) over the natural numbers and general linear orders. We show that the satisfiability problem remains non-elementary over linear orders, but its complexity drops to PSPACE-completeness over natural numbers. We categorize the strict fragments arising from different combinations of modal and hybrid operators into NP-complete and tractable, and show that the latter cases are complete for NC1 or LOGSPACE. Interestingly, NP-completeness depends only on the fragment and not on the frame. For the cases above NP, satisfiability over linear orders is harder than over natural numbers, while below NP it is at most as hard. In addition ...

  10. A Review on Potentiality of Nano Filler/Natural Fiber Filled Polymer Hybrid Composites

    Directory of Open Access Journals (Sweden)

    Naheed Saba

    2014-08-01

    Full Text Available The increasing demand for greener and biodegradable materials leading to the satisfaction of society requires a compelling towards the advancement of nano-materials science. The polymeric matrix materials with suitable and proper filler, better filler/matrix interaction together with advanced and new methods or approaches are able to develop polymeric composites which shows great prospective applications in constructions and buildings, automotive, aerospace and packaging industries. The biodegradability of the natural fibers is considered as the most important and interesting aspects of their utilization in polymeric materials. Nanocomposite shows considerable applications in different fields because of larger surface area, and greater aspect ratio, with fascinating properties. Being environmentally friendly, applications of nanocomposites offer new technology and business opportunities for several sectors, such as aerospace, automotive, electronics, and biotechnology industries. Hybrid bio-based composites that exploit the synergy between natural fibers in a nano-reinforced bio-based polymer can lead to improved properties along with maintaining environmental appeal. This review article intended to present information about diverse classes of natural fibers, nanofiller, cellulosic fiber based composite, nanocomposite, and natural fiber/nanofiller-based hybrid composite with specific concern to their applications. It will also provide summary of the emerging new aspects of nanotechnology for development of hybrid composites for the sustainable and greener environment.

  11. Scouring Process of Natural Color Cotton Products

    Institute of Scientific and Technical Information of China (English)

    XU Wei

    2002-01-01

    In order to improve the absorbency of color cotton products, alkali and pectase scouring processes under different conditions were tested, by comparing the actual results of two different scouring processes. It was considered that the pectase scouring process more suits color cotton products.

  12. Hybrid fusion reactor for production of nuclear fuel with minimum radioactive contamination of the fuel cycle

    Science.gov (United States)

    Velikhov, E. P.; Kovalchuk, M. V.; Azizov, E. A.; Ignatiev, V. V.; Subbotin, S. A.; Tsibulskiy, V. F.

    2015-12-01

    The paper presents the results of the system research on the coordinated development of nuclear and fusion power engineering in the current century. Considering the increasing problems of resource procurement, including limited natural uranium resources, it seems reasonable to use fusion reactors as high-power neutron sources for production of nuclear fuel in a blanket. It is shown that the share of fusion sources in this structural configuration of the energy system can be relatively small. A fundamentally important aspect of this solution to the problem of closure of the fuel cycle is that recycling of highly active spent fuel can be abandoned. Radioactivity released during the recycling of the spent fuel from the hybrid reactor blanket is at least two orders of magnitude lower than during the production of the same number of fissile isotopes after the recycling of the spent fuel from a fast reactor.

  13. Consumer animosity in the global value chain: The effect of international production shifts on willingness to purchase hybrid products

    OpenAIRE

    Charles A Funk; Jonathan D Arthurs; Len J Treviño; Jeff Joireman

    2010-01-01

    The escalation of international offshoring and outsourcing in recent years has resulted in a proliferation of “hybrid products” for the typical multinational enterprise, with multiple country affiliations for branding, design, manufacture, assembly and parts sourcing. However, little has been written regarding the impact of consumer animosity on such hybrid activities, or the role of universal values in a hybrid production animosity model. In this paper we extend the consumer animosity litera...

  14. Comparative genomics among Saccharomyces cerevisiae × Saccharomyces kudriavzevii natural hybrid strains isolated from wine and beer reveals different origins

    Science.gov (United States)

    2012-01-01

    Background Interspecific hybrids between S. cerevisiae × S. kudriavzevii have frequently been detected in wine and beer fermentations. Significant physiological differences among parental and hybrid strains under different stress conditions have been evidenced. In this study, we used comparative genome hybridization analysis to evaluate the genome composition of different S. cerevisiae × S. kudriavzevii natural hybrids isolated from wine and beer fermentations to infer their evolutionary origins and to figure out the potential role of common S. kudriavzevii gene fraction present in these hybrids. Results Comparative genomic hybridization (CGH) and ploidy analyses carried out in this study confirmed the presence of individual and differential chromosomal composition patterns for most S. cerevisiae × S. kudriavzevii hybrids from beer and wine. All hybrids share a common set of depleted S. cerevisiae genes, which also are depleted or absent in the wine strains studied so far, and the presence a common set of S. kudriavzevii genes, which may be associated with their capability to grow at low temperatures. Finally, a maximum parsimony analysis of chromosomal rearrangement events, occurred in the hybrid genomes, indicated the presence of two main groups of wine hybrids and different divergent lineages of brewing strains. Conclusion Our data suggest that wine and beer S. cerevisiae × S. kudriavzevii hybrids have been originated by different rare-mating events involving a diploid wine S. cerevisiae and a haploid or diploid European S. kudriavzevii strains. Hybrids maintain several S. kudriavzevii genes involved in cold adaptation as well as those related to S. kudriavzevii mitochondrial functions. PMID:22906207

  15. A natural driven membrane process for brackish and wastewater treatment: photovoltaic powered ED and FO hybrid system.

    Science.gov (United States)

    Zhang, Yang; Pinoy, Luc; Meesschaert, Boudewijn; Van der Bruggen, Bart

    2013-09-17

    In isolated locations, remote areas, or islands, potable water is precious because of the lack of drinking water treatment facilities and energy supply. Thus, a robust and reliable water treatment system based on natural energy is needed to reuse wastewater or to desalinate groundwater/seawater for provision of drinking water. In this work, a hybrid membrane system combining electrodialysis (ED) and forward osmosis (FO), driven by renewable energy (solar energy), denoted as EDFORD (ED-FO Renewable energy Desalination), is proposed to produce high-quality water (potable) from secondary wastewater effluent or brackish water. In this hybrid membrane system, feedwater (secondary wastewater effluent or synthetic brackish water) was drawn to the FO draw solution while the organic and inorganic substances (ions, compounds, colloids and particles) were rejected. The diluted draw solution was then pumped to the solar energy driven ED. In the ED unit, the diluted draw solution was desalted and high-quality water was produced; the concentrate was recycled to the FO unit and reused as the draw solution. Results show that the water produced from this system contains a low concentration of total organic carbon (TOC), carbonate, and cations derived from the feedwater; had a low conductivity; and meets potable water standards. The water production cost considering the investment for membranes and solar panel is 3.32 to 4.92 EUR m(-3) (for 300 days of production per year) for a small size potable water production system.

  16. New natural products as new leads for antibacterial drug discovery.

    Science.gov (United States)

    Brown, Dean G; Lister, Troy; May-Dracka, Tricia L

    2014-01-15

    Natural products have been a rich source of antibacterial drugs for many decades, but investments in this area have declined over the past two decades. The purpose of this review article is to provide a recent survey of new natural product classes and the mechanisms by which they work.

  17. Rapid Growth in China Natural Gas Demand and Production

    Institute of Scientific and Technical Information of China (English)

    Li Min

    2003-01-01

    @@ China's natural gas production will exceed 35 billion cubic meters in 2003,more than 7 percent up from last year,according to the estimation by the related department. There are now more than 60 enterprises engaged in natural gas production in China.

  18. China Ranks 15th for 2001 Natural Gas Production

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ China's natural gas output totaled 30.302 billion cubic meters in 2001, an 11 percent increase as compared with the previous year. However, China ranked 15th in the world for its natural gas production last year while Malaysia jumped to the 12th place in the ranking since the country saw a considerable increase in gas production.

  19. Harnessing natural product assembly lines: structure, promiscuity, and engineering.

    Science.gov (United States)

    Ladner, Christopher C; Williams, Gavin J

    2016-03-01

    Many therapeutically relevant natural products are biosynthesized by the action of giant mega-enzyme assembly lines. By leveraging the specificity, promiscuity, and modularity of assembly lines, a variety of strategies has been developed that enables the biosynthesis of modified natural products. This review briefly summarizes recent structural advances related to natural product assembly lines, discusses chemical approaches to probing assembly line structures in the absence of traditional biophysical data, and surveys efforts that harness the inherent or engineered promiscuity of assembly lines for the synthesis of non-natural polyketides and non-ribosomal peptide analogues.

  20. Quantitative assessment of toxic and nontoxic Microcystis colonies in natural environments using fluorescence in situ hybridization and flow cytometry

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Toxic cyanobacterial blooms constitute a threat to human safety because Microcystis sp. releases microcystins during growth, and particularly during cell death. Therefore, analysis of toxic and nontoxic Microcystis in natural communities is required in order to assess and predict bloom dynamics and toxin production by these organisms. In this study, an analysis combining fluorescence in situ hybridization (FISH) with flow cytometry (FCM) was used to discriminate between toxic and nontoxic Microcystis and also to quantify the percentage of toxic Microcystis present in blooms. The results demonstrate that the combination of FISH and flow cytometry is a useful approach for studying the ecology of Microcystis toxin production and for providing an early warning for toxic Microcystis blooms.

  1. Psychoactive natural products: overview of recent developments

    OpenAIRE

    2014-01-01

    Natural psychoactive substances have fascinated the curious mind of shamans, artists, scholars and laymen since antiquity. During the twentieth century, the chemical composition of the most important psychoactive drugs, that is opium, cannabis, coca and "magic mushrooms", has been fully elucidated. The mode of action of the principal ingredients has also been deciphered at the molecular level. In the past two decades, the use of herbal drugs, such as kava, kratom and Salvia divinorum, began t...

  2. Genome mining unveils widespread natural product biosynthetic capacity in human oral microbe Streptococcus mutans

    Science.gov (United States)

    Liu, Liwei; Hao, Tingting; Xie, Zhoujie; Horsman, Geoff P.; Chen, Yihua

    2016-01-01

    Streptococcus mutans is a major pathogen causing human dental caries. As a Gram-positive bacterium with a small genome (about 2 Mb) it is considered a poor source of natural products. Due to a recent explosion in genomic data available for S. mutans strains, we were motivated to explore the natural product production potential of this organism. Bioinformatic characterization of 169 publically available genomes of S. mutans from human dental caries revealed a surprisingly rich source of natural product biosynthetic gene clusters. Anti-SMASH analysis identified one nonribosomal peptide synthetase (NRPS) gene cluster, seven polyketide synthase (PKS) gene clusters and 136 hybrid PKS/NRPS gene clusters. In addition, 211 ribosomally synthesized and post-translationally modified peptides (RiPPs) clusters and 615 bacteriocin precursors were identified by a combined analysis using BAGEL and anti-SMASH. S. mutans harbors a rich and diverse natural product genetic capacity, which underscores the importance of probing the human microbiome and revisiting species that have traditionally been overlooked as “poor” sources of natural products. PMID:27869143

  3. Recent Advances in Separation of Bioactive Natural Products

    Institute of Scientific and Technical Information of China (English)

    任其龙; 邢华斌; 鲍宗必; 苏宝根; 杨启炜; 杨亦文; 张治国

    2013-01-01

    Bioactive natural products are a main source of new drugs, functional foods and food additives. The separation of bioactive natural products plays an important role in transformation and use of biomass. The isolation and purification of bioactive principle from a complex matrix is often inherent bottleneck for the utilization of natural products, so a series of extraction and separation techniques have been developed. This review covers recent advances in the separation of bioactive natural products with an emphasis on their solubility and diffusion coeffi-cients, recent extraction techniques and isolation techniques. This overview of recent technological advances, dis-cussion of pertinent problems and prospect of current methodologies in the separation of bioactive natural products may provide a driving force for development of novel separation techniques.

  4. Bioactive natural products from Papua New Guinea marine sponges.

    Science.gov (United States)

    Noro, Jeffery C; Kalaitzis, John A; Neilan, Brett A

    2012-10-01

    The discovery of novel natural products for drug development relies heavily upon a rich biodiversity, of which the marine environment is an obvious example. Marine natural product research has spawned several drugs and many other candidates, some of which are the focus of current clinical trials. The sponge megadiversity of Papua New Guinea is a rich but underexplored source of bioactive natural products. Here, we review some of the many natural products derived from PNG sponges with an emphasis on those with interesting biological activity and, therefore, drug potential. Many bioactive natural products discussed here appear to be derived from non-ribosomal peptide and polyketide biosynthesis pathways, strongly suggesting a microbial origin of these compounds. With this in mind, we also explore the notion of sponge-symbiont biosynthesis of these bioactive compounds and present examples to support the working hypothesis.

  5. Marinopyrroles: Unique Drug Discoveries Based on Marine Natural Products.

    Science.gov (United States)

    Li, Rongshi

    2016-01-01

    Natural products provide a successful supply of new chemical entities (NCEs) for drug discovery to treat human diseases. Approximately half of the NCEs are based on natural products and their derivatives. Notably, marine natural products, a largely untapped resource, have contributed to drug discovery and development with eight drugs or cosmeceuticals approved by the U.S. Food and Drug Administration and European Medicines Agency, and ten candidates undergoing clinical trials. Collaborative efforts from drug developers, biologists, organic, medicinal, and natural product chemists have elevated drug discoveries to new levels. These efforts are expected to continue to improve the efficiency of natural product-based drugs. Marinopyrroles are examined here as a case study for potential anticancer and antibiotic agents.

  6. Capturing Biological Activity in Natural Product Fragments by Chemical Synthesis.

    Science.gov (United States)

    Crane, Erika A; Gademann, Karl

    2016-03-14

    Natural products have had an immense influence on science and have directly led to the introduction of many drugs. Organic chemistry, and its unique ability to tailor natural products through synthesis, provides an extraordinary approach to unlock the full potential of natural products. In this Review, an approach based on natural product derived fragments is presented that can successfully address some of the current challenges in drug discovery. These fragments often display significantly reduced molecular weights, reduced structural complexity, a reduced number of synthetic steps, while retaining or even improving key biological parameters such as potency or selectivity. Examples from various stages of the drug development process up to the clinic are presented. In addition, this process can be leveraged by recent developments such as genome mining, antibody-drug conjugates, and computational approaches. All these concepts have the potential to identify the next generation of drug candidates inspired by natural products.

  7. Antimycobacterial susceptibility testing methods for natural products research

    Directory of Open Access Journals (Sweden)

    Juan Gabriel Bueno Sánchez

    2010-06-01

    Full Text Available The emergence of multidrug-resistant strains of Mycobacterium tuberculosis underscores the need of continuous developments on new and efficient methods to determine the susceptibility of isolates of M. tuberculosis in the search for novel antimicrobial agents. Natural products constitute an important source of new drugs, but design and implementation of antimycobacterial susceptibility testing methods are necessary for evaluate the different extracts and compounds. A number of biological assay methodologies are in current use, ranging from the classical disk diffusion and broth dilution assay format, to radiorespirometric (BACTEC, dye-based, and fluorescent/luminescence reporter assays. This review presents an analysis on the in vitro susceptibility testing methods developed for determinate antitubercular activity in natural products and related compounds (semi-synthetic natural products and natural products-derived compounds and the criteria to select the adequate method for determination of biological activity of new natural products.

  8. MARINE NATURAL PRODUCTS: A WAY TO NEW DRUGS

    OpenAIRE

    Stonik, V.

    2009-01-01

    The investigation of marine natural products (low molecular weight bioregulators) is a rapidly developing scientific field at the intersection of biology and chemistry. Investigations aimed at detecting, identifying, and understanding the structure of marine natural products have led to the discovery of 20,000 new substances, including those characterized by an extremely high physiological activity. Some results and prospects of works aimed at creating new drugs on the basis of marine natural...

  9. Marine actinobacteria: new opportunities for natural product search and discovery.

    Science.gov (United States)

    Bull, Alan T; Stach, James E M

    2007-11-01

    It is widely accepted that new drugs, especially antibiotics, are urgently required, and that the most propitious source remains natural products. We argue that in exploring new sources of bioactive natural products the marine environment warrants particular attention, in view of the remarkable diversity of microorganisms and metabolic products. Recent reports of new chemical entities and first-in-class drug candidates, and confirmation of indigenous marine actinobacteria, make exciting discoveries even more likely given the unrivalled capacity of this class of bacteria to produce exploitable natural products.

  10. The structural biology of enzymes involved in natural product glycosylation.

    Science.gov (United States)

    Singh, Shanteri; Phillips, George N; Thorson, Jon S

    2012-10-01

    The glycosylation of microbial natural products often dramatically influences the biological and/or pharmacological activities of the parental metabolite. Over the past decade, crystal structures of several enzymes involved in the biosynthesis and attachment of novel sugars found appended to natural products have emerged. In many cases, these studies have paved the way to a better understanding of the corresponding enzyme mechanism of action and have served as a starting point for engineering variant enzymes to facilitate to production of differentially-glycosylated natural products. This review specifically summarizes the structural studies of bacterial enzymes involved in biosynthesis of novel sugar nucleotides.

  11. Chern-Simons production during preheating in hybrid inflation models

    CERN Document Server

    García-Bellido, J; González-Arroyo, A; Garcia-Bellido, Juan; Perez, Margarita Garcia; Gonzalez-Arroyo, Antonio

    2004-01-01

    We study the onset of symmetry breaking after hybrid inflation in a model having the field content of the SU(2) gauge-scalar sector of the standard model, coupled to a singlet inflaton. This process is studied in (3+1)-dimensions in a fully non-perturbative way with the help of lattice techniques within the classical approximation. We focus on the role played by gauge fields and, in particular, on the generation of Chern-Simons number. Our results are shown to be insensitive to the various cut-offs introduced in our numerical approach. The spectra preserves a large hierarchy between long and short-wavelength modes during the whole period of symmetry breaking and Chern-Simons generation, confirming that the dynamics is driven by the low momentum sector of the theory. We establish that the Chern-Simons production mechanism is associated with local sphaleron-like structures. The corresponding sphaleron rates are of order 10^{-5} m^{-4}, which, within certain scenarios of electroweak baryogenesis and a (not unnat...

  12. Hybridization accompanying FRET event in labeled natural nucleoside-unnatural nucleoside containing chimeric DNA duplexes.

    Science.gov (United States)

    Bag, Subhendu Sekhar; Das, Suman K; Pradhan, Manoj Kumar; Jana, Subhashis

    2016-09-01

    Förster resonance energy transfer (FRET) is a highly efficient strategy in illuminating the structures, structural changes and dynamics of DNA, proteins and other biomolecules and thus is being widely utilized in studying such phenomena, in designing molecular/biomolecular probes for monitoring the hybridization event of two single stranded DNA to form duplex, in gene detection and in many other sensory applications in chemistry, biology and material sciences. Moreover, FRET can give information about the positional status of chromophores within the associated biomolecules with much more accuracy than other methods can yield. Toward this end, we want to report here the ability of fluorescent unnatural nucleoside, triazolylphenanthrene ((TPhen)BDo) to show FRET interaction upon hybridization with fluorescently labeled natural nucleosides, (Per)U or (OxoPy)U or (Per)U, forming two stable chimeric DNA duplexes. The pairing selectivity and the thermal duplex stability of the chimeric duplexes are higher than any of the duplexes with natural nucleoside formed. The hybridization results in a Förster resonance energy transfer (FRET) from donor triazolylphenanthrene of (TPhen)BDo to acceptor oxopyrene of (OxoPy)U and/or to perylene chromophore of (Per)U, respectively, in two chimeric DNA duplexes. Therefore, we have established the FRET process in two chimeric DNA duplexes wherein a fluorescently labeled natural nucleoside ((OxoPy)U or (Per)U) paired against an unnatural nucleoside ((TPhen)BDo) without sacrificing the duplex stability and B-DNA conformation. The hybridization accompanying FRET event in these classes of interacting fluorophores is new. Moreover, there is no report of such designed system of chimeric DNA duplex. Our observed phenomenon and the design can potentially be exploited in designing more of such efficient FRET pairs for useful application in the detection and analysis of biomolecular interactions and in material science application. Copyright

  13. Strategies for target identification of antimicrobial natural products.

    Science.gov (United States)

    Farha, Maya A; Brown, Eric D

    2016-05-04

    Covering: 2000 to 2015Despite a pervasive decline in natural product research at many pharmaceutical companies over the last two decades, natural products have undeniably been a prolific and unsurpassed source for new lead antibacterial compounds. Due to their inherent complexity, natural extracts face several hurdles in high-throughout discovery programs, including target identification. Target identification and validation is a crucial process for advancing hits through the discovery pipeline, but has remained a major bottleneck. In the case of natural products, extremely low yields and limited compound supply further impede the process. Here, we review the wealth of target identification strategies that have been proposed and implemented for the characterization of novel antibacterials. Traditionally, these have included genomic and biochemical-based approaches, which, in recent years, have been improved with modern-day technology and better honed for natural product discovery. Further, we discuss the more recent innovative approaches for uncovering the target of new antibacterial natural products, which have resulted from modern advances in chemical biology tools. Finally, we present unique screening platforms implemented to streamline the process of target identification. The different innovative methods to respond to the challenge of characterizing the mode of action for antibacterial natural products have cumulatively built useful frameworks that may advocate a renovated interest in natural product drug discovery programs.

  14. Confirmation of natural hybrids between Gentiana straminea and G. siphonantha (Gentianaceae) based on molecular evidence

    Institute of Scientific and Technical Information of China (English)

    Xiaojuan LI; Liuyang WANG; Huiling YANG; Jianquan LIU

    2008-01-01

    A few individuals with intermediate morpho-logy always appeared in the sympatric distributions of Gentiana straminea and G. siphonantha. These intermedi-ate individuals were hypothesized to be the hybrids of two species after a careful evaluation of their morphological characteristics. To test this hypothesis, sequence compar-ison of the internal transcribed spacer (ITS) regions of the nuclear ribosomal and trnS (GCU)-trnG (UCC) inter-genic spacer region of the chloroplast DNA from Gentiana straminea, G. siphonantha and the putative hybrids was performed. The results suggest that most intermediate individuals were the natural hybrids between G. straminea and G. siphonantha. In addition, we exam-ined the sequence variation among the individuals of both parent species and analyzed the possibility leading to the incongruent identification in some individuals based on morphologic and molecular evidences, respectively. The intraspecific diversification of DNA fragments within both parent species and their high variability in hybrid swarms probably resulted from chloroplast genome recombination and incomplete lineage sorting during the early stages of speciation origin of the parent species.

  15. Detection of hybrids in nature: application to oaks (Quercus suber and Q. ilex).

    Science.gov (United States)

    Burgarella, C; Lorenzo, Z; Jabbour-Zahab, R; Lumaret, R; Guichoux, E; Petit, R J; Soto, A; Gil, L

    2009-05-01

    Powerful and accurate detection of first-generation (F1) hybrids and backcrosses in nature is needed to achieve a better understanding of the function and dynamics of introgression. To document the frequency of ongoing interspecific gene exchange between two Mediterranean evergreen oaks, the cork oak (Quercus suber) and the holm oak (Q. ilex), we analyzed 1487 individuals originating from across the range of the two species using eight microsatellite loci and two Bayesian clustering approaches (implemented in the programs STRUCTURE and NEWHYBRIDS). Simulated data were used to assess the differences between the two clustering methods and to back up the choice of the threshold value for the posterior probability to discriminate admixed from pure individuals. We found that the use of STRUCTURE resulted in the highest power to detect hybrids, whereas NEWHYBRIDS provided the highest accuracy. Irrespective of the approach, the two species were clearly distinguished as independent genetic entities without any prior information. In contrast with previous reports, we found no evidence for unidirectional introgression. The overall hybridization rate was very low (<2% of introgressed individuals). Only two individuals were identified as F1 hybrids and five as early backcrosses. This work shows that the combined application of the two complementary Bayesian approaches and their systematic validation with simulations, fit for the case at hand, helps gain resolution in the identification of admixed individuals.

  16. NATURAL ANTIOXIDANTS IN PRODUCTION “BRUSHWOOD”

    Directory of Open Access Journals (Sweden)

    G. N. Dubtsova

    2015-01-01

    Full Text Available Flour wares use popularity, there is 48% of general volume of pastry wares on their stake. A marketing study on results that actuality of development of new type of flour good is set with the lowered maintenance of fat and enriched by vitamins is undertaken. The use of natural antioxidant of "Guarding is reasonable toco 70" and introduction of 0,2% is recommended for stabilizing of sunflower-seed oil at fry of frying. Joint introduction of powders is studied from the garden-stuffs of brier and unabi on quality of the brushwood fried in sunflower-seed oil with the use of "Guarding toco 70". From wares extracted lipids and estimated on indexes: peroxides, acid and anizid numbers. It is set that an antioxidant and vegetable powders assist the decline of indexes of safety peroxides and asid in two times, and anizid in 1,3 time. Use of antioxidant of "Guarding toco 70", being in 70% from the natural concentrate of mixture of tocopherolss and 30% of soyaoil.

  17. Photoactive Hybrid Catalysts Based on Natural and Synthetic Polymers: A Comparative Overview.

    Science.gov (United States)

    Colmenares, Juan Carlos; Kuna, Ewelina

    2017-05-12

    In the present review, we would like to draw the reader's attention to the polymer-based hybrid materials used in photocatalytic processes for efficient degradation of organic pollutants in water. These inorganic-organic materials exhibit unique physicochemical properties due to the synergistic effect originating from the combination of individual elements, i.e., photosensitive metal oxides and polymeric supports. The possibility of merging the structural elements of hybrid materials allows for improving photocatalytic performance through (1) an increase in the light-harvesting ability; (2) a reduction in charge carrier recombination; and (3) prolongation of the photoelectron lifetime. Additionally, the great majority of polymer materials exhibit a high level of resistance against ultraviolet irradiation and improved corrosion resistance. Taking into account that the chemical and environmental stability of the hybrid catalyst depends, to a great extent, on the functional support, we highlight benefits and drawbacks of natural and synthetic polymer-based photocatalytic materials and pay special attention to the fact that the accessibility of synthetic polymeric materials derived from petroleum may be impeded due to decreasing amounts of crude oil. Thus, it is necessary to look for cheap and easily available raw materials like natural polymers that come from, for instance, lignocellulosic wastes or crustacean residues to meet the demand of the "plastic" market.

  18. Fungi as a source of natural coumarins production.

    Science.gov (United States)

    Costa, Tania Maria; Tavares, Lorena Benathar Ballod; de Oliveira, Débora

    2016-08-01

    Natural coumarins and derivatives are compounds that occur naturally in several organisms (plant, bacteria, and fungi) consisting of fused benzene and α-pyrone rings. These compounds show high technological potential applications in agrochemical, food, pharmaceuticals, and cosmetics industries. Therefore, the need for bulk production of coumarins and the advancement of the chemical and pharmaceutical industries led to the development of synthetic coumarin. However, biotransformation process, synthetic bioengineering, metabolic engineering, and bioinformatics have proven effective in the production of natural products. Today, these biological systems are recognized as green chemistry innovation and business strategy. This review article aims to report the potential of fungi for synthesis of coumarin. These microorganisms are described as a source of natural products capable of synthesizing many bioactive metabolites. The features, classification, properties, and industrial applications of natural coumarins as well as new molecules obtained by basidiomycetes and ascomycetes fungi are reported in order to explore a topic not yet discussed in the scientific literature.

  19. A new experimental hybrid of cabbage suitable for early production

    Directory of Open Access Journals (Sweden)

    Červenski Janko

    2012-01-01

    Full Text Available The paper analyzes experimental hybrids of early cabbage developed at the Institute of Field and Vegetable Crops in the previous period. The hybrids were tested together for two years and then one (H17 was chosen and submitted to the Variety Commission of the Republic of Serbia. In 2011, the experimental hybrid H17 was officially released as an early cabbage hybrid and registered under the name of NS Mendo F1. The hybrid had been developed by crossing two early lines, one of which was sterile. It is characterized by a short growing season - 65 days from transplanting to harvest. The head weight ranges from 2.5 to 3.5 kg depending on the cultural practice applied. The head is light green in color, sweet-tasting, and suitable for fresh consumption. The hybrid’s traits that contributed significantly to the formation of the first principal component were in fact those that the breeders attach most importance to in their breeding programs. These are the traits that directly influence the market value of a new hybrid and make a given hybrid recognizable on the market. Most notable among such traits are head weight and the weight of the useful part of the head.[Projekat Ministarstva nauke Republike Srbije, br. TR 31030

  20. Chemical Biology of Microbial Anticancer Natural Products

    DEFF Research Database (Denmark)

    Bladt, Tanja Thorskov; Gotfredsen, Charlotte Held

    towards chronic lymphocytic leukemia (CLL) cells is crucial since CLL is considered as an incurable disease. To discover novel agents that targets CLL cells is complicated. CLL cells rapidly undergo apoptosis in vitro when they are removed from their natural microenvironment, even though they are long......Filamentous fungi and other microorganisms have amazing abilities to synthesize structural complex, diverse and unique small organic molecules. Many are bioactive and numerous compounds such as mycotoxins, antifungal, and anticancer agents have been reported in the literature within the last more......-living cells in vivo. Fortunately viability of CLL cells can be maintained in vitro by co-cultivation with stromal cells mimicking in vivo conditions. This has led to the development of a co-culture assay that is ideally suited for screening of NPs. The main goal of this study has been to discover fungal NPs...

  1. College of Natural Resources to offer Forest Products Marketing Workshop

    OpenAIRE

    Davis, Lynn

    2008-01-01

    Marketing has been called the backbone of successful forest products companies, yet many small businesses struggle with the marketing concept. Virginia Tech's College of Natural Resources continues its service to the forest products industry by presenting the fourteenth annual workshop on Forest Products Marketing, Oct. 23 through Oct. 24, at The Inn at Virginia Tech and Skelton Conference Center.

  2. A PRODUCT HYBRID GMRES ALGORITHM FOR NONSYMMETRIC LINEAR SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Bao-jiang Zhong

    2005-01-01

    It has been observed that the residual polynomials resulted from successive restarting cycles of GMRES(m) may differ from one another meaningfully. In this paper, it is further shown that the polynomials can complement one another harmoniously in reducing the iterative residual. This characterization of GMRES(m) is exploited to formulate an efficient hybrid iterative scheme, which can be widely applied to existing hybrid algorithms for solving large nonsymmetric systems of linear equations. In particular, a variant of the hybrid GMRES algorithm of Nachtigal, Reichel and Trefethen (1992) is presented. It is described how the new algorithm may offer significant performance improvements over the original one.

  3. Production of Fine Metallic Powders by Hybrid Atomization Process

    Science.gov (United States)

    Minagawa, Kazumi; Liu, Yunzhong; Kakisawa, Hideki; Halada, Kohmei

    Hybrid Atomization is a recently developed powder-making process that combines effectively free-fall gas atomization and centrifugal atomization. This technique can produce very fine spherical powders with mean diameters of around 10 micrometers, and in high yields. The present report discusses the concept and basic principles of hybrid atomization. Process experiments were carried out and the optimal processing conditions were obtained. The results show that the influences of processing parameters and optimum conditions differ greatly between the proposed and the conventional atomization processes. A new correlation of atomization equation applicable to hybrid atomization is proposed and discussed.

  4. A hybrid framework for verification of satellite precipitation products

    Science.gov (United States)

    Li, J.; Hsu, K.; AghaKouchak, A.; Sorooshian, S.

    2011-12-01

    Advances in satellite technology have led to the development of many remote-sensing algorithms to estimate precipitation at quasi-global scales. A number of satellite precipitation products are provided at high spatial and temporal resolutions that are suitable for short-term hydrologic applications. Several coordinated validation activities have been established to evaluate the accuracy of satellite precipitation. Traditional verification measures summarize pixel-to-pixel differences between observation and estimates. Object-based verification methods, however, extend pixel based validation to address errors related to spatial patterns and storm structure, such as the shape, volume, and distribution of precipitation rain-objects. In this investigation, a 2D watershed segmentation technique is used to identify rain storm objects and is further adopted in a hybrid verification framework to diagnose the storm-scale rainfall objects from both satellite-based precipitation estimates and ground observations (radar estimates). Five key scores are identified in the objective-based verification framework, including false alarm ratio, missing ratio, maximum of total interest, equal weight and weighted summation of total interest. These scores indicate the performance of satellite estimates with features extracted from the segmented storm objects. The proposed object-based verification framework was used to evaluate PERSIANN, PERSIANN-CCS, CMORPH, 3B42RT against NOAA stage IV MPE multi-sensor composite rain analysis. All estimates are evaluated at 0.25°x0.25° daily-scale in summer 2008 over the continental United States (CONUS). The five final scores for each precipitation product are compared with the median of maximum interest (MMI) of the Method for Object-Based Diagnostic Evaluation (MODE). The results show PERSIANN and CMORPH outperform 3B42RT and PERSIANN-CCS. Different satellite products presented distinct features of precipitation. For example, the sizes of

  5. Polyhydroxyalkanoate-based natural synthetic hybrid copolymer films: A small-angle neutron scattering study

    Science.gov (United States)

    Foster, L. John R.; Knott, Robert; Sanguanchaipaiwong, Vorapat; Holden, Peter J.

    2006-11-01

    Polyhydroxyalkanoates have attracted attention as biodegradable alternatives to conventional thermoplastics and as biomaterials. Through modification of their biosynthesis using Pseudomonas oleovorans, we have manipulated the material properties of these biopolyesters and produced a natural-synthetic hybrid copolymer of polyhydroxyoctanoate- block-diethylene glycol (PHO- b-DEG). A mixture of PHO and PHO-DEG were solvent cast from analytical grade chloroform and analysed using small-angle neutron scattering. A scattering pattern, easily distinguished above the background, was displayed by the films with a diffraction ring at q∼0.12 Å -1. This narrow ring of intensity is suggestive of a highly ordered system. Analysis of the diffraction pattern supported this concept and showed a d-spacing of approximately 50 Å. In addition, conformation of the hybrid polymer chains can be manipulated to support their self-assembly into ordered microporous films.

  6. Polyhydroxyalkanoate-based natural-synthetic hybrid copolymer films: A small-angle neutron scattering study

    Energy Technology Data Exchange (ETDEWEB)

    Foster, L. John R. [Bio/polymer Research Group and Centre for Advanced Macromolecular Design, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney NSW2052 (Australia)]. E-mail: J.Foster@unsw.edu.au; Knott, Robert [Bragg Institute, Institute for Nuclear Geophysiology, Australian Nucelar Science and Technology Organisation, Menai NSW2234 (Australia); Sanguanchaipaiwong, Vorapat [Bio/polymer Research Group and Centre for Advanced Macromolecular Design, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney NSW2052 (Australia); Holden, Peter J. [Institute for Nuclear Geophysiology, Australian Nucelar Science and Technology Organisation, Menai NSW2234 (Australia)

    2006-11-15

    Polyhydroxyalkanoates have attracted attention as biodegradable alternatives to conventional thermoplastics and as biomaterials. Through modification of their biosynthesis using Pseudomonas oleovorans, we have manipulated the material properties of these biopolyesters and produced a natural-synthetic hybrid copolymer of polyhydroxyoctanoate-block-diethylene glycol (PHO-b-DEG). A mixture of PHO and PHO-DEG were solvent cast from analytical grade chloroform and analysed using small-angle neutron scattering. A scattering pattern, easily distinguished above the background, was displayed by the films with a diffraction ring at q{approx}0.12 A{sup -1}. This narrow ring of intensity is suggestive of a highly ordered system. Analysis of the diffraction pattern supported this concept and showed a d-spacing of approximately 50 A. In addition, conformation of the hybrid polymer chains can be manipulated to support their self-assembly into ordered microporous films.

  7. Culture, nature and particulate matter - Hybrid reframings in air pollution scholarship

    Science.gov (United States)

    Cupples, Julie

    Air pollution is a thoroughly hybrid phenomenon. It is composed of inseparable physical, scientific, cultural, social, economic and political dimensions. It is both an object of environmental science and embedded in our everyday social and cultural worlds. Nevertheless, much air pollution scholarship focuses solely on the physical dimensions of air pollution which are expressed quantitatively and pays little or no regard to the identities, discourses, bodies and emotions which constitute and are constituted by air pollution as a physical reality. This article argues for a more reflexive and hybrid approach to air pollution research which bridges intellectually confining binaries. Drawing on the work of Bruno Latour and other actor-network theorists, it argues that if we can let go of a foundational nature, disrupt our humanism and take non-scientific knowledges seriously, we might develop a new respect for the atmospheric environment and begin the task of building a better common world.

  8. Separation process design for isolation and purification of natural products

    DEFF Research Database (Denmark)

    Malwade, Chandrakant R.

    Natural products are defined as secondary metabolites produced by plants and form a vast pool of compounds with unlimited chemical and functional diversity. Many of these secondary metabolites are high value added chemicals that are frequently used as ingredients in food, cosmetics, pharmaceutica...... information is used to further optimize the process flow sheet. Chemometric methods have been used to extract molecular level information for understanding the process streams in relation to their separation operations....... and other consumer products. Therefore, process technology towards industrial scale production of such high value chemicals from plants has significant value. Natural products can be obtained in pure form via synthetic or semi-synthetic route, but due to their complicated nature these methods have not been...... developed to the extent of industrial production for majority of natural products. Thus, isolation and purification of such natural products from plants is the most viable way to obtain natural products in pure form. This PhD project is mainly concerned with the design of separation process to isolate...

  9. Radiation use efficiency, biomass production, and grain yield in two maize hybrids differing in drought tolerance

    Science.gov (United States)

    Drought tolerant (DT) maize (Zea mays L.) hybrids have potential to increase yield under drought conditions. However, little information is known about the physiological determinations of yield in DT hybrids. Our objective was to assess radiation use efficiency (RUE), biomass production, and yield ...

  10. Dereplication of Microbial Natural Products by LC-DAD-TOFMS

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Månsson, Maria; Rank, Christian;

    2011-01-01

    Dereplication, the rapid identification of known compounds present in a mixture, is crucial to the fast discovery of novel natural products. Determining the elemental composition of compounds in mixtures and tentatively identifying natural products using MS/MS and UV/vis spectra is becoming easier...... with advances in analytical equipment and better compound databases. Here we demonstrate the use of LC-UV/vis-MS-based dereplication using data from UV/vis diode array detection and ESI+/ESI– time-of-flight MS for assignment of 719 microbial natural product and mycotoxin reference standards. ESI+ was the most...

  11. Solid-phase enrichment and analysis of electrophilic natural products

    Directory of Open Access Journals (Sweden)

    Frank Wesche

    2017-03-01

    Full Text Available In search for new natural products, which may lead to the development of new drugs for all kind of applications, novel methods are needed. Here we describe the identification of electrophilic natural products in crude extracts via their reactivity against azide as a nucleophile followed by their subsequent enrichment using a cleavable azide-reactive resin (CARR. Using this approach, natural products carrying epoxides and α,β-unsaturated enones as well as several unknown compounds were identified in crude extracts from entomopathogenic Photorhabdus bacteria.

  12. Production of Substitute Natural Gas from Coal

    Energy Technology Data Exchange (ETDEWEB)

    Andrew Lucero

    2009-01-31

    The goal of this research program was to develop and demonstrate a novel gasification technology to produce substitute natural gas (SNG) from coal. The technology relies on a continuous sequential processing method that differs substantially from the historic methanation or hydro-gasification processing technologies. The thermo-chemistry relies on all the same reactions, but the processing sequences are different. The proposed concept is appropriate for western sub-bituminous coals, which tend to be composed of about half fixed carbon and about half volatile matter (dry ash-free basis). In the most general terms the process requires four steps (1) separating the fixed carbon from the volatile matter (pyrolysis); (2) converting the volatile fraction into syngas (reforming); (3) reacting the syngas with heated carbon to make methane-rich fuel gas (methanation and hydro-gasification); and (4) generating process heat by combusting residual char (combustion). A key feature of this technology is that no oxygen plant is needed for char combustion.

  13. Manufacturing Natural Killer Cells as Medicinal Products

    Science.gov (United States)

    Chabannon, Christian; Mfarrej, Bechara; Guia, Sophie; Ugolini, Sophie; Devillier, Raynier; Blaise, Didier; Vivier, Eric; Calmels, Boris

    2016-01-01

    Natural Killer (NK) cells are innate lymphoid cells (ILC) with cytotoxic and regulatory properties. Their functions are tightly regulated by an array of inhibitory and activating receptors, and their mechanisms of activation strongly differ from antigen recognition in the context of human leukocyte antigen presentation as needed for T-cell activation. NK cells thus offer unique opportunities for new and improved therapeutic manipulation, either in vivo or in vitro, in a variety of human diseases, including cancers. NK cell activity can possibly be modulated in vivo through direct or indirect actions exerted by small molecules or monoclonal antibodies. NK cells can also be adoptively transferred following more or less substantial modifications through cell and gene manufacturing, in order to empower them with new or improved functions and ensure their controlled persistence and activity in the recipient. In the present review, we will focus on the technological and regulatory challenges of NK cell manufacturing and discuss conditions in which these innovative cellular therapies can be brought to the clinic. PMID:27895646

  14. Hybrid microcircuit technology handbook materials, processes, design, testing and production

    CERN Document Server

    Licari, James J

    1998-01-01

    The Hybrid Microcircuit Technology Handbook integrates the many diverse technologies used in the design, fabrication, assembly, and testing of hybrid segments crucial to the success of producing reliable circuits in high yields. Among these are: resistor trimming, wire bonding, die attachment, cleaning, hermetic sealing, and moisture analysis. In addition to thin films, thick films, and assembly processes, important chapters on substrate selections, handling (including electrostatic discharge), failure analysis, and documentation are included. A comprehensive chapter of design guidelines will

  15. Hybridizing Cultural Understandings of the Natural World to Foster Critical Science Literacy

    Science.gov (United States)

    Tang, Kok Sing

    Adolescents are constantly exposed to multiple cultural views of the natural world in juxtaposition with the dominant view of science taught in school. This dissertation explores the interaction of these multiple views, and how they shape students' understanding of and attitudes toward science. Situated in a high school physics classroom, a curricular approach was designed and enacted to open a space in the classroom for the convergence of multiple discourses (or systems of cultural knowledge), and subsequently study how students navigate around them. Ethnographic and critical inquiry revealed that when two or more discourses about similar natural events or objects (e.g., toss of a colorguard flag, human body) were directly juxtaposed in the classroom space, conceptual, affective, and ideological conflicts were generated for certain students. This was particularly so for students whose embedded experiences and social affiliations within certain discourse communities (e.g., sport clubs, church) led to their preferred ways of looking at the natural world from one particular discourse, and consequently a negative stance toward alternative ways in other discourses. However, through appropriate pedagogical design and support, such juxtaposition also created opportunities for some students to hybridize different cultural understandings of the natural world as they navigated around multiple discourses. Informed by Bakhtin's notions of heteroglossia and voice appropriation, the characteristics of such hybridization were found to include: (a) being aware of heteroglossic differences in the use of language, (b) a dynamic shift in identification toward the dialogic other, (c) a juxtaposition of the other's voices in one's utterances, and (d) a momentary suppression of one's preferences, for strategic motives. Not only did hybridization provide a means for some students to construct conceptual knowledge across discourses, but it also helped them develop critical literacy in

  16. Opportunities for natural products in 21(st) century antibiotic discovery.

    Science.gov (United States)

    Wright, Gerard D

    2017-07-01

    Natural products and their derivatives are mainstays of our antibiotic drugs, but they are increasingly in peril. The combination of widespread multidrug resistance in once susceptible bacterial pathogens, disenchantment with natural products as sources of new drugs, lack of success using synthetic compounds and target-based discovery methods, along with shifting economic and regulatory issues, conspire to move investment in research and development away from the antibiotics arena. The result is a growing crisis in antibiotic drug discovery that threatens modern medicine. 21(st) century natural product research is perfectly positioned to fill the antibiotic discovery gap and bring new drug candidates to the clinic. Innovations in genomics and techniques to explore new sources of antimicrobial chemical matter are revealing new chemistry. Increasing appreciation of the value of narrow-spectrum drugs and re-examination of once discarded chemical scaffolds coupled with synthetic biology methods to generate new compounds and improve yields offer new strategies to revitalize once moribund natural product programs. The increasing awareness that the combination of antibiotics with adjuvants, non-antibiotic compounds that overcome resistance and enhance drug activity, can rescue older chemical scaffolds, and concepts such as blocking pathogen virulence present orthogonal strategies to traditional antibiotics. In all these areas, natural products offer chemical matter, shaped by natural selection, that is privileged in this therapeutic area. Natural product research is poised to regain prominence in delivering new drugs to solve the antibiotic crisis.

  17. Raman spectra of carotenoids in natural products

    Science.gov (United States)

    Withnall, Robert; Chowdhry, Babur Z.; Silver, Jack; Edwards, Howell G. M.; de Oliveira, Luiz F. C.

    2003-08-01

    Resonance Raman spectra of naturally occurring carotenoids have been obtained from nautilus, periwinkle ( Littorina littorea) and clam shells under 514.5 nm excitation and these spectra are compared with the resonance Raman spectra obtained in situ from tomatoes, carrots, red peppers and saffron. The tomatoes, carrots and red peppers gave rise to resonance Raman spectra exhibiting a ν1 band at ca. 1520 cm -1, in keeping with its assignment to carotenoids with ca. nine conjugated carboncarbon double bonds in their main chains, whereas the resonance Raman spectrum of saffron showed a ν1 band at 1537 cm -1 which can be assigned to crocetin, having seven conjugated carboncarbon double bonds. A correlation between ν1 wavenumber location and effective conjugated chain length has been used to interpret the data obtained from the shells, and the wavenumber position (1522 cm -1) of the ν1 band of the carotenoid in the orange clam shell suggests that it contains nine conjugated double bonds in the main chain. However, the black periwinkle and nautilus shells exhibit ν1 bands at 1504 and 1496 cm -1, respectively. On the basis of the correlation between ν1 wavenumber location and effective conjugated chain length, this indicates that they contain carotenoids with longer conjugated chains, the former having ca. 11 double bonds and the latter ca. 13 or even more. Raman spectra of the nautilus, periwinkle and clam shells also exhibited a strong band at 1085 cm -1 and a doublet with components at 701 and 705 cm -1, which can be assigned to biogenic calcium carbonate in the aragonite crystallographic form.

  18. Natural and within-farmland biodiversity enhances crop productivity.

    Science.gov (United States)

    Carvalheiro, Luísa Gigante; Veldtman, Ruan; Shenkute, Awraris Getachew; Tesfay, Gebreamlak Bezabih; Pirk, Christian Walter Werner; Donaldson, John Sydney; Nicolson, Susan Wendy

    2011-03-01

    Ongoing expansion of large-scale agriculture critically threatens natural habitats and the pollination services they offer. Creating patches with high plant diversity within farmland is commonly suggested as a measure to benefit pollinators. However, farmers rarely adopt such practice, instead removing naturally occurring plants (weeds). By combining pollinator exclusion experiments with analysis of honeybee behaviour and flower-visitation webs, we found that the presence of weeds allowed pollinators to persist within sunflower fields, maximizing the benefits of the remaining patches of natural habitat to productivity of this large-scale crop. Weed diversity increased flower visitor diversity, hence ameliorating the measured negative effects of isolation from natural habitat. Although honeybees were the most abundant visitors, diversity of flower visitors enhanced honeybee movement, being the main factor influencing productivity. Conservation of natural patches combined with promoting flowering plants within crops can maximize productivity and, therefore, reduce the need for cropland expansion, contributing towards sustainable agriculture.

  19. Reinvigorating natural product combinatorial biosynthesis with synthetic biology.

    Science.gov (United States)

    Kim, Eunji; Moore, Bradley S; Yoon, Yeo Joon

    2015-09-01

    Natural products continue to play a pivotal role in drug-discovery efforts and in the understanding if human health. The ability to extend nature's chemistry through combinatorial biosynthesis--altering functional groups, regiochemistry and scaffold backbones through the manipulation of biosynthetic enzymes--offers unique opportunities to create natural product analogs. Incorporating emerging synthetic biology techniques has the potential to further accelerate the refinement of combinatorial biosynthesis as a robust platform for the diversification of natural chemical drug leads. Two decades after the field originated, we discuss the current limitations, the realities and the state of the art of combinatorial biosynthesis, including the engineering of substrate specificity of biosynthetic enzymes and the development of heterologous expression systems for biosynthetic pathways. We also propose a new perspective for the combinatorial biosynthesis of natural products that could reinvigorate drug discovery by using synthetic biology in combination with synthetic chemistry.

  20. Evidence of Natural Hybridization in Brazilian Wild Lineages of Saccharomyces cerevisiae.

    Science.gov (United States)

    Barbosa, Raquel; Almeida, Pedro; Safar, Silvana V B; Santos, Renata Oliveira; Morais, Paula B; Nielly-Thibault, Lou; Leducq, Jean-Baptiste; Landry, Christian R; Gonçalves, Paula; Rosa, Carlos A; Sampaio, José Paulo

    2016-01-18

    The natural biology of Saccharomyces cerevisiae, the best known unicellular model eukaryote, remains poorly documented and understood although recent progress has started to change this situation. Studies carried out recently in the Northern Hemisphere revealed the existence of wild populations associated with oak trees in North America, Asia, and in the Mediterranean region. However, in spite of these advances, the global distribution of natural populations of S. cerevisiae, especially in regions were oaks and other members of the Fagaceae are absent, is not well understood. Here we investigate the occurrence of S. cerevisiae in Brazil, a tropical region where oaks and other Fagaceae are absent. We report a candidate natural habitat of S. cerevisiae in South America and, using whole-genome data, we uncover new lineages that appear to have as closest relatives the wild populations found in North America and Japan. A population structure analysis revealed the penetration of the wine genotype into the wild Brazilian population, a first observation of the impact of domesticated microbe lineages on the genetic structure of wild populations. Unexpectedly, the Brazilian population shows conspicuous evidence of hybridization with an American population of Saccharomyces paradoxus. Introgressions from S. paradoxus were significantly enriched in genes encoding secondary active transmembrane transporters. We hypothesize that hybridization in tropical wild lineages may have facilitated the habitat transition accompanying the colonization of the tropical ecosystem.

  1. Natural Product Polyamines That Inhibit Human Carbonic Anhydrases

    Directory of Open Access Journals (Sweden)

    Rohan A. Davis

    2014-01-01

    Full Text Available Natural product compound collections have proven an effective way to access chemical diversity and recent findings have identified phenolic, coumarin, and polyamine natural products as atypical chemotypes that inhibit carbonic anhydrases (CAs. CA enzymes are implicated as targets of variable drug therapeutic classes and the discovery of selective, drug-like CA inhibitors is essential. Just two natural product polyamines, spermine and spermidine, have until now been investigated as CA inhibitors. In this study, five more complex natural product polyamines 1–5, derived from either marine sponge or fungi, were considered for inhibition of six different human CA isozymes of interest in therapeutic drug development. All compounds share a simple polyamine core fragment, either spermine or spermidine, yet display substantially different structure activity relationships for CA inhibition. Notably, polyamines 1–5 were submicromolar inhibitors of the cancer drug target CA IX, this is more potent than either spermine or spermidine.

  2. Does species diversity limit productivity in natural grassland communities?

    NARCIS (Netherlands)

    Grace, James B.; Anderson, T. Michael; Smith, Melinda D.; Seabloom, Eric; Andelman, Sandy J.; Meche, Gayna; Weiher, Evan; Allain, Larry K.; Jutila, Heli; Sankaran, Mahesh; Knops, Johannes; Ritchie, Mark; Willig, Michael R.

    2007-01-01

    Theoretical analyses and experimental studies of synthesized assemblages indicate that under particular circumstances species diversity can enhance community productivity through niche complementarity. It remains unclear whether this process has important effects in mature natural ecosystems where c

  3. Revealing the macromolecular targets of complex natural products

    Science.gov (United States)

    Reker, Daniel; Perna, Anna M.; Rodrigues, Tiago; Schneider, Petra; Reutlinger, Michael; Mönch, Bettina; Koeberle, Andreas; Lamers, Christina; Gabler, Matthias; Steinmetz, Heinrich; Müller, Rolf; Schubert-Zsilavecz, Manfred; Werz, Oliver; Schneider, Gisbert

    2014-12-01

    Natural products have long been a source of useful biological activity for the development of new drugs. Their macromolecular targets are, however, largely unknown, which hampers rational drug design and optimization. Here we present the development and experimental validation of a computational method for the discovery of such targets. The technique does not require three-dimensional target models and may be applied to structurally complex natural products. The algorithm dissects the natural products into fragments and infers potential pharmacological targets by comparing the fragments to synthetic reference drugs with known targets. We demonstrate that this approach results in confident predictions. In a prospective validation, we show that fragments of the potent antitumour agent archazolid A, a macrolide from the myxobacterium Archangium gephyra, contain relevant information regarding its polypharmacology. Biochemical and biophysical evaluation confirmed the predictions. The results obtained corroborate the practical applicability of the computational approach to natural product ‘de-orphaning’.

  4. Does species diversity limit productivity in natural grassland communities?

    NARCIS (Netherlands)

    Grace, James B.; Anderson, T. Michael; Smith, Melinda D.; Seabloom, Eric; Andelman, Sandy J.; Meche, Gayna; Weiher, Evan; Allain, Larry K.; Jutila, Heli; Sankaran, Mahesh; Knops, Johannes; Ritchie, Mark; Willig, Michael R.

    Theoretical analyses and experimental studies of synthesized assemblages indicate that under particular circumstances species diversity can enhance community productivity through niche complementarity. It remains unclear whether this process has important effects in mature natural ecosystems where

  5. Nigerian Journal of Natural Products and Medicine - Vol 2 (1998)

    African Journals Online (AJOL)

    Nigerian Journal of Natural Products and Medicine - Vol 2 (1998) ... RESEARCH AND DEVELOPMENT INTO HERBAL MEDICINES · EMAIL FULL ... OF BRIDELIA FERRUGUBEA STEM BARK ON BLOOD CHEMISTRY AND HISTOLOGY OF ...

  6. Marine organisms: an alternative source of potentially valuable natural products

    Directory of Open Access Journals (Sweden)

    Alphonse Kelecom

    1991-01-01

    Full Text Available This paper recalls the outcoming of marine natural products research and reviews a selection of marirne bioactive metabolites in current use together with promising trends in marine pharmacology.

  7. Use of Brown Algae to Demonstrate Natural Products Techniques.

    Science.gov (United States)

    Porter, Lee A.

    1985-01-01

    Background information is provided on the natural products found in marine organisms in general and the brown algae in particular. Also provided are the procedures needed to isolate D-mannitol (a primary metabolite) and cholesterol from brown algae. (JN)

  8. Modular Power System Configured with Standard Product Hybrid DC-DC Converters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — VPT proposes an innovative concept whereby complex, multiple-output, DC-DC converter systems can be configured through use of only 2 standard product hybrid DC-DC...

  9. Journals on Traditional Medicine and Natural Products Published in English

    Institute of Scientific and Technical Information of China (English)

    CONG Wei-hong; CHEN Ke-ji

    2010-01-01

    @@ Due to better understanding of traditional medicine, complementary and alternative medicine, and natural products, there are increasing findings in these fields.In order to facilitate the findings to be known widely and timely by readers, here this article showed researchers some journals on traditional medicine, complementary and alternative medicine,and natural products, published in English and tracked by Thomson Reuters (ISI) in 2009, as well as some influential journals untracked by ISI.

  10. Marine natural products sourced from marine-derived Penicillium fungi.

    Science.gov (United States)

    Ma, Hong-Guang; Liu, Qiang; Zhu, Guo-Liang; Liu, Hai-Shan; Zhu, Wei-Ming

    2016-01-01

    Marine micro-organisms have been proven to be a major source of marine natural products (MNPs) in recent years, in which filamentous fungi are a vital source of bioactive natural products for their large metagenomes and more complex genetic backgrounds. This review highlights the 390 new MNPs from marine-derived Penicillium fungi during 1991 to 2014. These new MNPs are categorized based on the environment sources of the fungal hosts and their bioactivities are summarized.

  11. Emerging trends in the discovery of natural product antibacterials

    DEFF Research Database (Denmark)

    Bologa, Cristian G; Ursu, Oleg; Oprea, Tudor;

    2013-01-01

    mechanisms. Special emphasis is given to the strengths, weaknesses, and opportunities in the natural product antibacterial drug discovery arena, and to emerging applications driven by advances in bioinformatics, chemical biology, and synthetic biology in concert with exploiting bacterial phenotypes....... These efforts have identified a critical mass of natural product antibacterial lead compounds and discovery technologies with high probability of successful implementation against emerging bacterial pathogens....

  12. Total synthesis and biological activity of natural product Urukthapelstatin A.

    Science.gov (United States)

    Lin, Chun-Chieh; Tantisantisom, Worawan; McAlpine, Shelli R

    2013-07-19

    Herein we report the first total synthesis of the natural product Urkuthaplestatin A (Ustat A) utilizing a convergent synthetic strategy. The characterization and biological activity match those of the previously published natural product. Interestingly, several intermediates, including the linear and serine cyclized precursors, show a 100-fold decrease in cytotoxicity, with IC50's in the low micromolar range. These data indicate that the rigidity and the consecutive aromatic heterocyclic system are responsible for the biological activity.

  13. Case Studies of the Synthesis of Bioactive Cyclodepsipeptide Natural Products

    Directory of Open Access Journals (Sweden)

    Markus Kaiser

    2013-01-01

    Full Text Available Cyclodepsipeptide natural products often display intriguing biological activities that along with their complex molecular scaffolds, makes them interesting targets for chemical synthesis. Although cyclodepsipeptides feature highly diverse chemical structures, their synthesis is often associated with similar synthetic challenges such as the establishment of a suitable macrocyclization methodology. This review therefore compiles case studies of synthetic approaches to different bioactive cyclodepsipeptide natural products, thereby illustrating obstacles of cyclodepsipeptide synthesis as well as their overcomings.

  14. Hybrid Aluminum and Natural Fiber Composite Structure for Crash Safety Improvement

    Science.gov (United States)

    Helaili, S.; Chafra, M.; Chevalier, Y.

    There is a growing interest on pedestrian's protection in automotive safety standards. Pedestrians head impact is one of the most important tests. In this paper, a hybrid composite structure made from natural fiber and aluminum, which improve the head protection when impact is taken place, is presented. The structure is made from a honeycomb composite made from unidirectional and woven composites and a thin aluminum layer. A head impact model is developed. The number of hexagonal layers is fixed and the thickness of the aluminum layer of the honeycomb structure is varied. The specific absorption energy is then calculated.

  15. A Hybrid Natural Transform Homotopy Perturbation Method for Solving Fractional Partial Differential Equations

    Directory of Open Access Journals (Sweden)

    Shehu Maitama

    2016-01-01

    Full Text Available A hybrid analytical method for solving linear and nonlinear fractional partial differential equations is presented. The proposed analytical approach is an elegant combination of the Natural Transform Method (NTM and a well-known method, Homotopy Perturbation Method (HPM. In this analytical method, the fractional derivative is computed in Caputo sense and the nonlinear term is calculated using He’s polynomial. The proposed analytical method reduces the computational size and avoids round-off errors. Exact solution of linear and nonlinear fractional partial differential equations is successfully obtained using the analytical method.

  16. Chitosan-graft-poly(n-butyl acrylate) copolymer: Synthesis and characterization of a natural/synthetic hybrid material.

    Science.gov (United States)

    Anbinder, Pablo; Macchi, Carlos; Amalvy, Javier; Somoza, Alberto

    2016-07-10

    Two chitosan polymers with different deacetylation degree and molecular weight were subjected to grafting reactions with the aim to enhance the properties of these bio-based materials. Specifically, n-butyl acrylate in different proportions was grafted onto two different deacetylation degree (DD%) chitosan using radical initiation in a surfactant free emulsion system. Infrared spectroscopy was used to confirm grafting and products grafting percentage and efficiency were evaluated against acrylate/chitosan ratio and DD%. Thermal and structural properties and the behavior against water of the raw and grafted biopolymers were studied using several experimental techniques: differential scanning calorimetry, transmission electron microscopy, dynamic light scattering, water swelling, contact angle and positron annihilation lifetime spectroscopy. The influence of the grafting process on the morphological and physicochemical properties of the prepared natural/synthetic hybrid materials is discussed.

  17. Anti-Enterovirus 71 Agents of Natural Products

    Directory of Open Access Journals (Sweden)

    Liyan Wang

    2015-09-01

    Full Text Available This review, with 42 references, presents the fascinating area of anti-enterovirus 71 natural products over the last three decades for the first time. It covers literature published from 2005–2015 and refers to compounds isolated from biogenic sources. In total, 58 naturally-occurring anti-EV71 compounds are recorded.

  18. Biotechnological production of natural zero-calorie sweeteners.

    Science.gov (United States)

    Philippe, Ryan N; De Mey, Marjan; Anderson, Jeff; Ajikumar, Parayil Kumaran

    2014-04-01

    The increasing public awareness of adverse health impacts from excessive sugar consumption has created increasing interest in plant-derived, natural low-calorie or zero-calorie sweeteners. Two plant species which contain natural sweeteners, Stevia rebaudiana and Siraitia grosvenorii, have been extensively profiled to identify molecules with high intensity sweetening properties. However, sweetening ability does not necessarily make a product viable for commercial applications. Some criteria for product success are proposed to identify which targets are likely to be accepted by consumers. Limitations of plant-based production are discussed, and a case is put forward for the necessity of biotechnological production methods such as plant cell culture or microbial fermentation to meet needs for commercial-scale production of natural sweeteners.

  19. Creation of Hybrid Nanorods From Sequences of Natural Trimeric Fibrous Proteins Using the Fibritin Trimerization Motif

    Science.gov (United States)

    Papanikolopoulou, Katerina; van Raaij, Mark J.; Mitraki, Anna

    Stable, artificial fibrous proteins that can be functionalized open new avenues in fields such as bionanomaterials design and fiber engineering. An important source of inspiration for the creation of such proteins are natural fibrous proteins such as collagen, elastin, insect silks, and fibers from phages and viruses. The fibrous parts of this last class of proteins usually adopt trimeric, β-stranded structural folds and are appended to globular, receptor-binding domains. It has been recently shown that the globular domains are essential for correct folding and trimerization and can be successfully substituted by a very small (27-amino acid) trimerization motif from phage T4 fibritin. The hybrid proteins are correctly folded nanorods that can withstand extreme conditions. When the fibrous part derives from the adenovirus fiber shaft, different tissue-targeting specificities can be engineered into the hybrid proteins, which therefore can be used as gene therapy vectors. The integration of such stable nanorods in devices is also a big challenge in the field of biomechanical design. The fibritin foldon domain is a versatile trimerization motif and can be combined with a variety of fibrous motifs, such as coiled-coil, collagenous, and triple β-stranded motifs, provided the appropriate linkers are used. The combination of different motifs within the same fibrous molecule to create stable rods with multiple functions can even be envisioned. We provide a comprehensive overview of the experimental procedures used for designing, creating, and characterizing hybrid fibrous nanorods using the fibritin trimerization motif.

  20. Strong natural selection on juveniles maintains a narrow adult hybrid zone in a broadcast spawner.

    Science.gov (United States)

    Prada, Carlos; Hellberg, Michael E

    2014-12-01

    Natural selection can maintain and help form species across different habitats, even when dispersal is high. Selection against inferior migrants (immigrant inviability) acts when locally adapted populations suffer high mortality on dispersal to unsuitable habitats. Habitat-specific populations undergoing divergent selection via immigrant inviability should thus show (1) a change in the ratio of adapted to nonadapted individuals among age/size classes and (2) a cline (defined by the environmental gradient) as selection counterbalances migration. Here we examine the frequencies of two depth-segregated lineages in juveniles and adults of a Caribbean octocoral, Eunicea flexuosa. Distributions of the two lineages in both shallow and deep environments were more distinct when inferred from adults than juveniles. Despite broad larval dispersal, we also found an extremely narrow hybrid zone (<100 m), with coincident clines for molecular and morphological characters of the host coral and its algal symbiont. Effective dispersal estimates derived from the hybrid zone are remarkably small (<20 m) for a broadcast spawner. The large selection coefficient against mismatched genotypes derived from cohort data is consistent with that from field transplant experiments. Narrow hybrid zones and limited effective dispersal may be a common outcome of long periods of postsettlement, prereproductive selection across steep ecological gradients. Strong diversifying selection provides a mechanism to explain the prevalence of depth-segregated sibling species in the sea.

  1. Relative contribution of dispersal and natural selection to the maintenance of a hybrid zone in Littorina.

    Science.gov (United States)

    Cruz, Raquel; Vilas, Carlos; Mosquera, Javier; García, Carlos

    2004-12-01

    Habitat preference behavior may play an important role in nonallopatric speciation. However, most examples of habitat preference contributing to differentiation within natural populations correspond to parasites or herbivores living in the discrete environments constituted by their animal or plant hosts. In the present study we investigated migration guided by habitat preference in the intertidal snail Littorina saxatilis in a hybrid zone associated with an ecotone across the shore, which is therefore a continuously varying environment. First, we found evidence for this behavior in one of the two locations studied. Second, we made reciprocal transplants to suppress the phenotypic gradient observed across the hybrid zone and measured the relative contributions of selection and migration to its regeneration. Selection played an important role at the two locations studied, but migration was only important at one, where it accounted for between a third and a half of the regenerated gradient. This overall minor effect of migration was relevant for theoretical models dealing with nonallopatric speciation, because it suggested that variation for habitat preference did not have an important role in the initiation of the differentiation process. The preference behavior observed in the hybrid zone would have evolved secondarily, as a consequence of habitat-dependent fitness differences between phenotypes.

  2. Using the SPoRT POES/GOES Hybrid Product in OCONUS Forecasting

    Science.gov (United States)

    Smith, Matt; Fuell, Kevin; Nelson, Jim

    2014-01-01

    The SPoRT (Short-term Prediction and Research Transition) Program at the NASA/Marshall Space Flight Center has been providing unique NASA and NOAA data and techniques to partner Weather Forecast Offices (WFOs) for ten years. Data are provided in the Decision Support System used by WFO forecasters: AWIPS. For the last couple of years, SPoRT has been producing the POES/GOES Hybrid. This suite of products combines the strength ofl5- minute animations of GOES imagery - providing temporal continuity, with the higher resolution, relatively random availability, of polar orbiting (POES) imagery data. The product was first introduced with only MODIS data from NASA's Terra and Aqua satellites, but recently the VIIRS instrument onboard the Suomi-NPP satellite was added, providing better high-resolution coverage. These products represent SPoRT's efforts to prepare for higher resolution, higher frequency GOES-R imagery - as well as helping to move VIIRS (JPSS) data into the mainstream of weather forecasting. SPoRT generates 5 products for this dataset: Visible, Longwave Infrared (11 micrometers), Shortwave IR (3.7 micrometers), Water Vapor (6.7 micrometers), and Fog (Difference of 11 micrometer and 3.7 micrometer channels). The Water Vapor hybrid product has a Red-Blue-Green image from MODIS inlaid, since it provides even more qualitative information than water vapor alone. Animated examples of the products will be shown in this presentation. While the resolution at nadir of GOES imagery is nominally Han (4km for IR channels), the inlaid polar orbiter imagery has a resolution of 250m (lkm for IR channels). This has tremendous application in the continental US. However, in high latitudes, since the usefulness of GOES degrades poleward rapidly, the contrast of GOES and POES data is stark. The consistent temporal nature of GOES, even though at a reduced resolution at high latitudes, provides basic situational awareness, but the introduction of polar data is very helpful in seeing

  3. The sustainable management of a productive natural capital

    DEFF Research Database (Denmark)

    Daubanes, Julien Xavier

    This paper examines an industry whose economic activity uses a natural capital on which its profit also relies. When such a productive natural capital has a limited capacity to recover from its exploitation, a free market tends to over-exploit it, calling for public intervention. The analysis...... is relevant, among other examples, to the case of naturebased tourism. I study the sustainable management of a productive natural capital: the conditions under which its exploitation generates maximum long-run social benefits; the various ways in which a regulator can implement such an exploitation; the rent...

  4. Fusion-Fission Hybrid for Fissile Fuel Production without Processing

    Energy Technology Data Exchange (ETDEWEB)

    Fratoni, M; Moir, R W; Kramer, K J; Latkowski, J F; Meier, W R; Powers, J J

    2012-01-02

    Two scenarios are typically envisioned for thorium fuel cycles: 'open' cycles based on irradiation of {sup 232}Th and fission of {sup 233}U in situ without reprocessing or 'closed' cycles based on irradiation of {sup 232}Th followed by reprocessing, and recycling of {sup 233}U either in situ or in critical fission reactors. This study evaluates a third option based on the possibility of breeding fissile material in a fusion-fission hybrid reactor and burning the same fuel in a critical reactor without any reprocessing or reconditioning. This fuel cycle requires the hybrid and the critical reactor to use the same fuel form. TRISO particles embedded in carbon pebbles were selected as the preferred form of fuel and an inertial laser fusion system featuring a subcritical blanket was combined with critical pebble bed reactors, either gas-cooled or liquid-salt-cooled. The hybrid reactor was modeled based on the earlier, hybrid version of the LLNL Laser Inertial Fusion Energy (LIFE1) system, whereas the critical reactors were modeled according to the Pebble Bed Modular Reactor (PBMR) and the Pebble Bed Advanced High Temperature Reactor (PB-AHTR) design. An extensive neutronic analysis was carried out for both the hybrid and the fission reactors in order to track the fuel composition at each stage of the fuel cycle and ultimately determine the plant support ratio, which has been defined as the ratio between the thermal power generated in fission reactors and the fusion power required to breed the fissile fuel burnt in these fission reactors. It was found that the maximum attainable plant support ratio for a thorium fuel cycle that employs neither enrichment nor reprocessing is about 2. This requires tuning the neutron energy towards high energy for breeding and towards thermal energy for burning. A high fuel loading in the pebbles allows a faster spectrum in the hybrid blanket; mixing dummy carbon pebbles with fuel pebbles enables a softer spectrum in

  5. Natural product biosynthesis: It's all downhill from here

    Science.gov (United States)

    Hornsby, Charles E.; Paton, Robert S.

    2014-02-01

    High selectivity is essential in the enzymatic biosynthesis of complex natural products. Now, the discovery of multiple sequential bifurcations on the reaction path towards the formation of a diterpenoid shows how dynamics affect selectivity, and suggests how enzymes may steer reactions towards a specific product.

  6. Nature-Inspired Design: Strategies for Sustainable Product Development

    NARCIS (Netherlands)

    De Pauw, I.C.

    2015-01-01

    Product designers can apply different strategies, methods, and tools for sustainable product development. Nature-Inspired Design Strategies (NIDS) offer designers a distinct class of strategies that use ‘nature’ as a guiding source of knowledge and inspiration for addressing sustainability. Biomimic

  7. Nature-Inspired Design: Strategies for Sustainable Product Development

    NARCIS (Netherlands)

    De Pauw, I.C.

    2015-01-01

    Product designers can apply different strategies, methods, and tools for sustainable product development. Nature-Inspired Design Strategies (NIDS) offer designers a distinct class of strategies that use ‘nature’ as a guiding source of knowledge and inspiration for addressing

  8. Nature-Inspired Design: Strategies for Sustainable Product Development

    NARCIS (Netherlands)

    De Pauw, I.C.

    2015-01-01

    Product designers can apply different strategies, methods, and tools for sustainable product development. Nature-Inspired Design Strategies (NIDS) offer designers a distinct class of strategies that use ‘nature’ as a guiding source of knowledge and inspiration for addressing sustainability. Biomimic

  9. Acidification Enhances Hybrid N2O Production Associated with Aquatic Ammonia-Oxidizing Microorganisms

    Science.gov (United States)

    Frame, Caitlin H.; Lau, Evan; Nolan, E. Joseph; Goepfert, Tyler J.; Lehmann, Moritz F.

    2017-01-01

    Ammonia-oxidizing microorganisms are an important source of the greenhouse gas nitrous oxide (N2O) in aquatic environments. Identifying the impact of pH on N2O production by ammonia oxidizers is key to understanding how aquatic greenhouse gas fluxes will respond to naturally occurring pH changes, as well as acidification driven by anthropogenic CO2. We assessed N2O production rates and formation mechanisms by communities of ammonia-oxidizing bacteria (AOB) and archaea (AOA) in a lake and a marine environment, using incubation-based nitrogen (N) stable isotope tracer methods with 15N-labeled ammonium (15NH4+) and nitrite (15NO2−), and also measurements of the natural abundance N and O isotopic composition of dissolved N2O. N2O production during incubations of water from the shallow hypolimnion of Lake Lugano (Switzerland) was significantly higher when the pH was reduced from 7.54 (untreated pH) to 7.20 (reduced pH), while ammonia oxidation rates were similar between treatments. In all incubations, added NH4+ was the source of most of the N incorporated into N2O, suggesting that the main N2O production pathway involved hydroxylamine (NH2OH) and/or NO2− produced by ammonia oxidation during the incubation period. A small but significant amount of N derived from exogenous/added 15NO2− was also incorporated into N2O, but only during the reduced-pH incubations. Mass spectra of this N2O revealed that NH4+ and 15NO2− each contributed N equally to N2O by a “hybrid-N2O” mechanism consistent with a reaction between NH2OH and NO2−, or compounds derived from these two molecules. Nitrifier denitrification was not an important source of N2O. Isotopomeric N2O analyses in Lake Lugano were consistent with incubation results, as 15N enrichment of the internal N vs. external N atoms produced site preferences (25.0–34.4‰) consistent with NH2OH-dependent hybrid-N2O production. Hybrid-N2O formation was also observed during incubations of seawater from coastal Namibia

  10. Screening strategies for discovery of antibacterial natural products.

    Science.gov (United States)

    Singh, Sheo B; Young, Katherine; Miesel, Lynn

    2011-08-01

    Microbial-derived natural products have been a traditional source of antibiotics and antibiotic leads and continue to be effective sources of antibiotics today. The most important of these discoveries were made about 50 years ago. Chemical modifications of natural products discovered during those years continue to produce new clinical agents but their value is now, unfortunately, fading away owing to the exhaustion of opportunities of chemical modifications. The discovery of new natural antibiotics is directly linked to new screening technologies, particularly technologies that can help to eliminate the rediscovery of known antibiotics. In this article, we have reviewed the screening technologies from recent literature as well as originating from authors laboratories that were used for the screening of natural products. The article covers the entire spectrum of screening strategies, including classical empiric whole-cell assays to more sophisticated antisense based hypersensitive Staphylococcus aureus Fitness Test assays designed to screen all targets simultaneously. These technologies have led to the discovery of a series of natural product antibiotics, which have been summarized, including the discovery of platensimycin, platencin, nocathiacins, philipimycin, cyclothialidine and muryamycins. It is quite clear that natural products provide a tremendous opportunity to discover new antibiotics when combined with new hyper-sensitive whole-cell technologies.

  11. Natural Products Towards the Discovery of Potential Future Antithrombotic Drugs.

    Science.gov (United States)

    Islam, Md Asiful; Alam, Fahmida; Khalil, Md Ibrahim; Sasongko, Teguh Haryo; Gan, Siew Hua

    2016-01-01

    Globally, thrombosis-associated disorders are one of the main contributors to fatalities. Besides genetic influences, there are some acquired and environmental risk factors dominating thrombotic diseases. Although standard regimens have been used for a long time, many side effects still occur which can be life threatening. Therefore, natural products are good alternatives. Although the quest for antithrombotic natural products came to light only since the end of last century, in the last two decades, a considerable number of natural products showing antithrombotic activities (antiplatelet, anticoagulant and fibrinolytic) with no or minimal side effects have been reported. In this review, several natural products used as antithrombotic agents including medicinal plants, vegetables, fruits, spices and edible mushrooms which have been discovered in the last 15 years and their target sites (thrombogenic components, factors and thrombotic pathways) are described. In addition, the side effects, limitations and interactions of standard regimens with natural products are also discussed. The active compounds could serve as potential sources for future research on antithrombotic drug development. As a future direction, more advanced researches (in quest of the target cofactor or component involved in antithrombotic pathways) are warranted for the development of potential natural antithrombotic medications (alone or combined with standard regimens) to ensure maximum safety and efficacy.

  12. Plant-Derived Natural Products for Parkinson's Disease Therapy.

    Science.gov (United States)

    Sengupta, T; Vinayagam, J; Singh, R; Jaisankar, P; Mohanakumar, K P

    2016-01-01

    Plant-derived natural products have made their own niche in the treatment of neurological diseases since time immemorial. Parkinson's disease (PD), the second most prevalent neurodegenerative disorder, has no cure and the treatment available currently is symptomatic. This chapter thoughtfully and objectively assesses the scientific basis that supports the increasing use of these plant-derived natural products for the treatment of this chronic and progressive disorder. Proper considerations are made on the chemical nature, sources, preclinical tests and their validity, and mechanisms of behavioural or biochemical recovery observed following treatment with various plants derived natural products relevant to PD therapy. The scientific basis underlying the neuroprotective effect of 6 Ayurvedic herbs/formulations, 12 Chinese medicinal herbs/formulations, 33 other plants, and 5 plant-derived molecules have been judiciously examined emphasizing behavioral, cellular, or biochemical aspects of neuroprotection observed in the cellular or animal models of the disease. The molecular mechanisms triggered by these natural products to promote cell survivability and to reduce the risk of cellular degeneration have also been brought to light in this study. The study helped to reveal certain limitations in the scenario: lack of preclinical studies in all cases barring two; heavy dependence on in vitro test systems; singular animal or cellular model to establish any therapeutic potential of drugs. This strongly warrants further studies so as to reproduce and confirm these reported effects. However, the current literature offers scientific credence to traditionally used plant-derived natural products for the treatment of PD.

  13. Effect of Silane Treatment on Hybridized Use of Short Cellulose Fibers and Silica Particles for Natural Rubber Reinforcement

    Science.gov (United States)

    Lopattananon, Natinee; Jitkalong, Dolmalik; Seadan, Manus; Sakai, Tadamoto

    Processability, swelling and tensile properties of natural-rubber-based hybrid composites prepared by mixing short cellulose fibers and fine silica particles of equal contents with total loading of 20 phr using a two-roll mill were analyzed. Their properties were compared with those of natural rubber reinforced with single filler (silica or cellulose fiber) and corresponding unfilled natural rubber. The tensile test showed the reinforcing effect of both single filler system and hybrid filler system in relation to natural rubber. The tensile modulus and tensile strength of hybrid composites generally laid between those of fiber-reinforced and silica-reinforced natural rubber composites, whereas the elongation at break of hybrid composites was equal to that of single filler reinforcement system. The Mooney viscosity of silica-filled compound was much higher than that of unfilled natural rubber and short fiber-filled compounds, and was significantly reduced when hybridized fillers were used. Furthermore, a silane coupling agent, Si 69, was used to modify the surface properties of cellulose fibers and silica particles. Three microscopic evaluation techniques, that is, elemental X-ray mapping (EDX), 3D microfocus X-ray scanning, and N-ARC methods were applied to investigate the filler dispersion/mixing effects. It was found that both of the fillers were more homogeneously dispersed in the hybrid composites, and the affinity between the fillers and natural rubber was improved after the silane treatment. The results from this work suggested that the better dispersion of short cellulose fiber/silica hybrid fillers had great advantages in rubber processing, and allowed for equal or higher composite strength compared to a simply silica-filled composite system.

  14. Importance of permanent improvement of production and control of basic seed of ZP maize hybrids

    Directory of Open Access Journals (Sweden)

    Sečanski Mile

    2015-01-01

    Full Text Available High-quality seed is one of the key factors in the commercial maize grain production. In addition, hybrid seed production is conditioned by the production of basic seed of parental inbreds. According to the Law on Seed, 2005, the category of basic seed is defined as: original of self-pollinated plant species, hybrid components and potato elite, produced under control of the Ministry competent for agribusiness and is used for the production of certified seed of the first generation. This paper presents a chronological overview of the overall activity since1945. that led to the modern production of maize seed in our country. The activities have been based on scientific, technical and technological achievements within many fields, ranging from genetics and breeding, through growing practices, processing, quality control and legal regulations concerning all of this. Transition from maize breeding and production to hybrids has provided an amazing development of maize breeding and seed production and also included significant profit. Therefore, maize seed production has become high-technology industry. The scientific and professional work in improving the production of basic seed of ZP maize hybrids has been carried out in stages, and generally followed achievements in maize breeding and genetics, as well as developments in the growing practices and processing. In order to maintain a high quality of maize hybrid seed, as the end product, permanent efforts have to be invested into maize production improvement, drying, processing, storing, genetic purity of basic seed of parental inbreds of ZP maize hybrids, which are grown on the significant percentage of maize production areas not only in Serbia and countries in the region.

  15. Chitin elicitation of natural product production in marine bacteria

    DEFF Research Database (Denmark)

    Månsson, Maria; Wietz, Matthias; Larsen, Thomas Ostenfeld

    Genome sequences reveal that our current standard laboratory conditions only support a fraction of the potential secondary metabolism in bacteria.1 Thus, we must rethink cultivation, detection, and isolation strategies for bacterial secondary metabolites in order to explore the huge, so far...... uncharacterized chemical potential of these organisms. As part of a new project on ecology-driven drug discovery at the Technical University of Denmark, we investigate the use of chitin to elicit or alter production of antibacterial compounds in marine bacteria. Within our large collection of Gram......-negative bacteria (mainly Pseudoalteromonas and Vibrio), we found that some strains were capable of producing antibacterial compounds when grown on chitin, an N-acetyl-D-glucosamine polymer found in the exoskeleton of zooplankton.2 A strain of Vibrio coralliilyticus solely produced the antibiotic andrimid,3...

  16. Comparative genomics among Saccharomyces cerevisiae × Saccharomyces kudriavzevii natural hybrid strains isolated from wine and beer reveals different origins

    Directory of Open Access Journals (Sweden)

    Peris David

    2012-08-01

    Full Text Available Abstract Background Interspecific hybrids between S. cerevisiae × S. kudriavzevii have frequently been detected in wine and beer fermentations. Significant physiological differences among parental and hybrid strains under different stress conditions have been evidenced. In this study, we used comparative genome hybridization analysis to evaluate the genome composition of different S. cerevisiae × S. kudriavzevii natural hybrids isolated from wine and beer fermentations to infer their evolutionary origins and to figure out the potential role of common S. kudriavzevii gene fraction present in these hybrids. Results Comparative genomic hybridization (CGH and ploidy analyses carried out in this study confirmed the presence of individual and differential chromosomal composition patterns for most S. cerevisiae × S. kudriavzevii hybrids from beer and wine. All hybrids share a common set of depleted S. cerevisiae genes, which also are depleted or absent in the wine strains studied so far, and the presence a common set of S. kudriavzevii genes, which may be associated with their capability to grow at low temperatures. Finally, a maximum parsimony analysis of chromosomal rearrangement events, occurred in the hybrid genomes, indicated the presence of two main groups of wine hybrids and different divergent lineages of brewing strains. Conclusion Our data suggest that wine and beer S. cerevisiae × S. kudriavzevii hybrids have been originated by different rare-mating events involving a diploid wine S. cerevisiae and a haploid or diploid European S. kudriavzevii strains. Hybrids maintain several S. kudriavzevii genes involved in cold adaptation as well as those related to S. kudriavzevii mitochondrial functions.

  17. Seasons and planting densities interaction on forage production of eight hybrids maize, Ecuador

    Directory of Open Access Journals (Sweden)

    Álvaro Cañadas L.

    2015-12-01

    Full Text Available Objective. To assess the interaction effect of the season and planting densities on the production of eight INIAP corn hybrids. Materials and methods. A research process was conducted in 2013. It was applied a split - split plot design with three replication and Tukey test was used. It was evaluated two planting seasons (28 January and 8 April, they were placed in large plots. Two planting densities (65,500 y 125,000 plants/ha, that were located in the subplots and eight INIAP corn hybrids arranged in the sub- subplots. The evaluated variables were Fresh Matter, Dry Matter, Plant Height and Crude Protein Results. Fresh Matter and Crude Protein productions were influenced by planting seasons. Plant densities affected the production of Fresh Matter, Dry Matter and Plant Height, as well as the interaction season by corn INIAP hybrids. While INIAP corn hybrids showed statistical differences in the production of Fresh, Dry Matter, Plant Height and Crude Protein. The eight INIAP hybrids productions were: Fresh Matter (58.86 ton/ha ±5.19; Dry Matter (21.45 ton/ha ±4.71; Plant Height (2.46 m ±0.16 and Crude Protein (10.6±1.12. Conclusions. The performance showed by hybrids INIAP CML-172, INIAP 6021 and INIAP 551 were very acceptable forage material and could be used for silage purposes.

  18. DOES PRODUCTIVITY MATTER IN THE ADOPTION OF HYBRID RICE? A COMPARATIVE STUDY

    Directory of Open Access Journals (Sweden)

    Rashed Saeed

    2013-12-01

    Full Text Available The present study was designed to analyze comparative economics of hybrid rice and basmati in the core rice growing area of Punjab. Cross-data was collected through well-structured questionnaires from 80 farmers during May and June 2011.Study results reveal that higher yield and less time required for maturity in production were the main reasons for planting of hybrid rice. Hybrid rice occupied 3.6 acres whereas area under basmati was 5.9 acres of the total farm area. Farmers obtained above 60 percent increase in yield of hybrid rice. Results show that cost of production of basmati rice was estimated as Rs.37364 per acre and total revenue was Rs.44768 per acre. The benefit cost ratio of basmati rice was 1.20 and that of hybrid rice was 1.80, implying that hybrid rice has brought comparatively more economic benefits to the farmers as compared to basmati in the study area. Shortage of buyers, much costly poor quality hybrid seed, late payment and higher transportation costs are among major constraints in rice production and marketing.

  19. Natural hybrids of the madtoms, Noturus flavus and Noturus insignis, from the Monongahela River drainage, West Virginia

    Science.gov (United States)

    Welsh, S.A.; Cincotta, Dan A.

    2004-01-01

    Natural hybridization is rare in the family Ictaluridae. Putative hybrids of the madtoms Noturus flavus and N. insignis were collected from Blackwater River, Monongahela River drainage, WV. Noturus flavus is native to the Monongahela River drainage, whereas N. insignis is nonnative. We quantified morphological differences among N. flavus, N. insignis, and putative hybrids by sheared principal components analysis of morphometric characters. Putative hybrids were intermediate in tooth patch dimensions, caudal fin pigmentation, length of the dorsal fin base, distance between the adipose/caudal notch and base of caudal fin, and position of anal fin. Hybridization between N. flavus and N. insignis is supported by morphological intermediacy, and may be linked to higher abundances of N. insignis or degraded habitat in the Blackwater River.

  20. Computer-Aided Drug Design of Bioactive Natural Products.

    Science.gov (United States)

    Prachayasittikul, Veda; Worachartcheewan, Apilak; Shoombuatong, Watshara; Songtawee, Napat; Simeon, Saw; Prachayasittikul, Virapong; Nantasenamat, Chanin

    2015-01-01

    Natural products have been an integral part of sustaining civilizations because of their medicinal properties. Past discoveries of bioactive natural products have relied on serendipity, and these compounds serve as inspiration for the generation of analogs with desired physicochemical properties. Bioactive natural products with therapeutic potential are abundantly available in nature and some of them are beyond exploration by conventional methods. The effectiveness of computational approaches as versatile tools for facilitating drug discovery and development has been recognized for decades, without exception, in the case of natural products. In the post-genomic era, scientists are bombarded with data produced by advanced technologies. Thus, rendering these data into knowledge that is interpretable and meaningful becomes an essential issue. In this regard, computational approaches utilize the existing data to generate knowledge that provides valuable understanding for addressing current problems and guiding the further research and development of new natural-derived drugs. Furthermore, several medicinal plants have been continuously used in many traditional medicine systems since antiquity throughout the world, and their mechanisms have not yet been elucidated. Therefore, the utilization of computational approaches and advanced synthetic techniques would yield great benefit to improving the world's health population and well-being.

  1. The Traditional Medicine and Modern Medicine from Natural Products

    Directory of Open Access Journals (Sweden)

    Haidan Yuan

    2016-04-01

    Full Text Available Natural products and traditional medicines are of great importance. Such forms of medicine as traditional Chinese medicine, Ayurveda, Kampo, traditional Korean medicine, and Unani have been practiced in some areas of the world and have blossomed into orderly-regulated systems of medicine. This study aims to review the literature on the relationship among natural products, traditional medicines, and modern medicine, and to explore the possible concepts and methodologies from natural products and traditional medicines to further develop drug discovery. The unique characteristics of theory, application, current role or status, and modern research of eight kinds of traditional medicine systems are summarized in this study. Although only a tiny fraction of the existing plant species have been scientifically researched for bioactivities since 1805, when the first pharmacologically-active compound morphine was isolated from opium, natural products and traditional medicines have already made fruitful contributions for modern medicine. When used to develop new drugs, natural products and traditional medicines have their incomparable advantages, such as abundant clinical experiences, and their unique diversity of chemical structures and biological activities.

  2. The Traditional Medicine and Modern Medicine from Natural Products.

    Science.gov (United States)

    Yuan, Haidan; Ma, Qianqian; Ye, Li; Piao, Guangchun

    2016-04-29

    Natural products and traditional medicines are of great importance. Such forms of medicine as traditional Chinese medicine, Ayurveda, Kampo, traditional Korean medicine, and Unani have been practiced in some areas of the world and have blossomed into orderly-regulated systems of medicine. This study aims to review the literature on the relationship among natural products, traditional medicines, and modern medicine, and to explore the possible concepts and methodologies from natural products and traditional medicines to further develop drug discovery. The unique characteristics of theory, application, current role or status, and modern research of eight kinds of traditional medicine systems are summarized in this study. Although only a tiny fraction of the existing plant species have been scientifically researched for bioactivities since 1805, when the first pharmacologically-active compound morphine was isolated from opium, natural products and traditional medicines have already made fruitful contributions for modern medicine. When used to develop new drugs, natural products and traditional medicines have their incomparable advantages, such as abundant clinical experiences, and their unique diversity of chemical structures and biological activities.

  3. Capillary electrophoresis of natural products: 2011-2012.

    Science.gov (United States)

    Tubaon, Ria Marni S; Rabanes, Heide; Haddad, Paul R; Quirino, Joselito P

    2014-01-01

    Bioactive natural products are major sources of lead compounds for drug discovery and pharmaceutical development, therefore, innovative and current separation and characterization techniques are important for these compounds. Here, CE methods applied for the analysis of natural products published during 2011-2012 are reviewed. This is an updated version of an earlier review paper in this journal, which highlighted developments during 2006-2010. The major method developments over the review period centered on derivatization, chiral analysis, modes of detection, stacking or on-line sample concentration, and sample preparation (predominantly using extraction methods). The samples analyzed were herbal products, foods, soil, and biological samples. Developments also occurred in the areas of quality control, toxicology assessment, and enzyme-inhibitor screening. A table that summarizes the areas, source of natural product, nature of the bioactive analyte, CE conditions, LODs, and corresponding reference is provided. A short description on the theory of CE and insights on future activities of CE on natural products are also presented.

  4. Culture-independent discovery of natural products from soil metagenomes.

    Science.gov (United States)

    Katz, Micah; Hover, Bradley M; Brady, Sean F

    2016-03-01

    Bacterial natural products have proven to be invaluable starting points in the development of many currently used therapeutic agents. Unfortunately, traditional culture-based methods for natural product discovery have been deemphasized by pharmaceutical companies due in large part to high rediscovery rates. Culture-independent, or "metagenomic," methods, which rely on the heterologous expression of DNA extracted directly from environmental samples (eDNA), have the potential to provide access to metabolites encoded by a large fraction of the earth's microbial biosynthetic diversity. As soil is both ubiquitous and rich in bacterial diversity, it is an appealing starting point for culture-independent natural product discovery efforts. This review provides an overview of the history of soil metagenome-driven natural product discovery studies and elaborates on the recent development of new tools for sequence-based, high-throughput profiling of environmental samples used in discovering novel natural product biosynthetic gene clusters. We conclude with several examples of these new tools being employed to facilitate the recovery of novel secondary metabolite encoding gene clusters from soil metagenomes and the subsequent heterologous expression of these clusters to produce bioactive small molecules.

  5. An Innovative Methodology of Product Design from Nature

    Institute of Scientific and Technical Information of China (English)

    Hui-I Wen; Shu-jun Zhang; Kevin Hapeshi; Xiao-feng Wang

    2008-01-01

    Nature is an information sourcebeok of behaviour, function, colour and shape which can inspire visual design and invention. Studying the form and functional characteristics of a natural object can provide inspiration for product design and help to improve the marketability of manufactured products. The inspiration can be triggered either by direct observation or captured by threo-dimensional (3D) digitising techniques to obtain superficial information (geometry and colour). An art designer often creates a concept in the form of a two-dimensional (2D) sketch while engineering methods lead to a point cloud in 3D. Each has its limitations in that the art designer commonly lacks the knowledge to build a final product from a 2D sketch and the engineering designer's 3D point clouds may not be very beautiful. We propose a method for Product Design from Nature (PDN),coupling aesthetic intent and geometrical characteristics, exploring the interactions between designers and nature's systems in PDN. We believe that this approach would considerably reduce the lead time and cost of product design from nature.

  6. High Temperature Induced Glume Closure Resulted in Lower Fertility in Hybrid Rice Seed Production

    Science.gov (United States)

    Yan, Haoliang; Zhang, Binglin; Zhang, Yunbo; Chen, Xinlan; Xiong, Hui; Matsui, Tsutomu; Tian, Xiaohai

    2017-01-01

    Predicted climate changes, in particular, the increased dimension and frequency of heat waves, are expected to affect crop growth in the future seriously. Hybrid rice relies on seed production from male sterile and restorer lines. Experiments were conducted over two consecutive years to compare the high temperature tolerance of parents of different hybrid rice combinations, in terms of fertility rate, flowering pattern, pollination and physiological parameters of the lodicule. Three male sterile lines and a broad compatibility restorer line (as pollen donor and conventional variety as well) were grown to heading stage and then treated with average daily temperatures of 26°C (range 23–30°C), 28°C (25–32°C), and 30°C (26–34°C), respectively, continued for 5–7 days each in a natural light phytotron which simulated the local typical high temperature weather in the field. The results indicated that male sterile lines were more sensitive to high temperature than the restorer line for fertility rate, and the sensitivity varied between varieties. The fertility rate of the restorer line was maintained at about 90% under the high temperature treatments, while it decreased in the male sterile lines by 23.3 and 48.1% at 28 and 30°C, respectively. The fertility rate of the most sensitive line declined by 70%, and the tolerant line declined by 34% at 30°C. Glume closure in the male sterile lines was a major reason for the reduced fertility rate under high temperature, which is closely correlated with carbohydrates content and the vascular bundle pattern in the lodicule. The present study identified a useful trait to select male sterile lines with high temperature tolerance for seed production. PMID:28105031

  7. Potential antimalarials from African natural products: A reviw.

    Science.gov (United States)

    Lawal, Bashir; Shittu, Oluwatosin Kudirat; Kabiru, Adamu Yusuf; Jigam, Ali Audu; Umar, Maimuna Bello; Berinyuy, Eustace Bonghan; Alozieuwa, Blessing Uchenna

    2015-01-01

    Malaria remains an overwhelming infectious disease with significant health challenges in African and other endemic countries globally. Resistance to antimalarial drugs has become one of the most momentous challenges to human health, and thus has necessitated the hunt for new and effective drugs. Consequently, few decades have witnessed a surfeit of research geared to validate the effectiveness of commonly used traditionally medicines against malaria fever. The present review work focuses on documenting natural products from African whose activity has been reported in vivo or in vitro against malaria parasite. Literature was collected using electronic search of published articles (Google Scholar, PubMed, Medline, Sciencedirect, and Science domain) that report on antiplasmodial activity of natural products from differernts Africa region. A total of 652 plant taxa from 146 families, 134 isolated antimalarial compounds from 39 plants species, 2 herbal formulations and 4 insect/products were found to be reported in literature from 1996 to 2015. Plants species from family Asteraceae (11.04%), Fababceae (8.128%), Euphorbiaceae (5.52%), Rubiaceas (5.52%), and Apocyanaceae (5.214%), have received more scientific validation than others. African natural products possess remarkable healing properties as revealed in the various citations as promising antimalarial agents. Some of these natural products from Africa demonstrate high, promising or low activities against Plasmodium parasite. This study also shows that natural products from Africa have a huge amount of novel antimalarial compounds that could serve as a leads for the development of new and effective antiplasmodial drugs. However, in a view of bridging the gap in knowledge, clinical validation of these natural products are of paramount importance.

  8. Naturally occurring hybrids derived from γ-amino acids and sugars with potential tail to tail ether-bonds

    Science.gov (United States)

    Feng, Zi-Ming; Zhan, Zhi-Lai; Yang, Ya-Nan; Jiang, Jian-Shuang; Zhang, Pei-Cheng

    2016-05-01

    The basic substances of life include various amino acids and sugars. To search such molecules is the precondition to understand the essential nature. Here we reported four unprecedented hybrids of γ-amino acids and sugars from the roots of Ranunculus ternatus, which possess potential tail to tail ether-connected (6,6-ether-connected) modes in the sugar moiety. The structures of these hybrids were elucidated by extensive analyses of spectra and calculated electronic circular dichroism (ECD) method.

  9. In Situ Production of Graphene-Fiber Hybrid Structures

    DEFF Research Database (Denmark)

    Akia, Mandana; Cremar, Lee; Chipara, Mircea

    2017-01-01

    We report a scalable method to obtain a new material where large graphene sheets form webs linking carbon fibers. Film-fiber hybrid nonwoven mats are formed during fiber processing and converted to carbon structures after a simple thermal treatment. This contrasts with multistep methods that atte......We report a scalable method to obtain a new material where large graphene sheets form webs linking carbon fibers. Film-fiber hybrid nonwoven mats are formed during fiber processing and converted to carbon structures after a simple thermal treatment. This contrasts with multistep methods...... a capillarity effect that promoted the formation of thin veils, which become graphene sheets upon dehydration by sulfuric acid vapor followed by carbonization (at relatively low temperatures, below 800 °C). These veils extend over several micrometers within the pores of the fiber network, and consist...

  10. Evaluation of effectiveness of natural organic compounds removal from water in hybrid processes

    Directory of Open Access Journals (Sweden)

    Malczewska Beata

    2016-09-01

    Full Text Available Natural organic matter (Natural Organic Matter – NOM represents a mixture of diverse chemical structure and different properties. The humic substances constitute an important component of NOM, and they are responsible for water color and taste, also they can contribute to the formation of disinfection by-products (DBP. Therefore, removal of NOM is considered to be one of the important technological operations during water treatment.

  11. Establishment of new crops for the production of natural rubber.

    Science.gov (United States)

    van Beilen, Jan B; Poirier, Yves

    2007-11-01

    Natural rubber is a unique biopolymer of strategic importance that, in many of its most significant applications, cannot be replaced by synthetic alternatives. The rubber tree Hevea brasiliensis is the almost exclusive commercial source of natural rubber currently and alternative crops should be developed for several reasons, including: a disease risk to the rubber tree that could potentially decimate current production, a predicted shortage of natural rubber supply, increasing allergic reactions to rubber obtained from the Brazilian rubber tree and a general shift towards renewables. This review summarizes our knowledge of plants that can serve as alternative sources of natural rubber, of rubber biosynthesis and the scientific gaps that must be filled to bring the alternative crops into production.

  12. Production and molecular characterization of somatic hybrids between Pleurotus florida and Lentinula edodes.

    Science.gov (United States)

    Mallick, Pijush; Sikdar, Samir Ranjan

    2014-08-01

    Nine inter-generic somatic hybrids named as pfle were produced through PEG-mediated protoplast fusion between Pleurotus florida and Lentinula edodes using double selection method. Hybridity of the newly developed strains was established on the basis of colony morphology, mycelial growth, hyphal traits, fruit-body productivity and inter single sequence repeat (ISSR) marker profiling. Hybrid population was assessed with different phenotypic variables by one-way analysis of variance. Principal component matrices were analyzed for the six phenotypic variables in scatter plot showing maximum positive correlation between each variable for all strains examined. Six ISSR primers generated 66 reproducible fragments with 98.48 % polymorphism. The dendrogram thus created based on unweighted pair-group method with mathematic averages method of clustering and Euclidean distance which exhibited three major groups between the parents and pfle hybrids. Though P. florida parent remained in one group but it showed different degrees of genetic distance with all the hybrid lines belonging to the other two groups while L. edodes was most distantly related to all the hybrid lines. L. edodes specific sequence-rich ISSR amplicon was recorded in all the hybrid lines and in L. edodes but not in P. florida. All the fruit body generating pfle hybrid lines could produce basidiocarp on paddy straw in sub-tropical climate and showed phenotypic resemblance to the P. florida parent.

  13. Natural product modulators to overcome multidrug resistance in cancer.

    Science.gov (United States)

    Cort, Aysegul; Ozben, Tomris

    2015-01-01

    Multidrug resistance (MDR) is a condition that makes cells simultaneously unresponsive to different drugs, unrelated to their chemical structure and mechanism of action. MDR caused by the presence and overexpression of ABC transporters makes obstacles in cancer treatment and lower the effectiveness of chemotherapy. Natural products are investigated by many researchers as MDR modulators for their low toxicity and potent, selective behavior. When coadministered, MDR modulators compete with cytotoxic agents for binding to the active site of the membrane transporters and reduce drug efflux. Natural product-based drugs are important in struggling against drug resistance during cancer therapy. This review is focused on the potential mechanisms against drug resistance, the development of inhibitors for ABC drug transporters, natural product modulators, and nanoparticle drug delivery.

  14. Dietary Natural Products for Prevention and Treatment of Liver Cancer

    Science.gov (United States)

    Zhou, Yue; Li, Ya; Zhou, Tong; Zheng, Jie; Li, Sha; Li, Hua-Bin

    2016-01-01

    Liver cancer is the most common malignancy of the digestive system with high death rate. Accumulating evidences suggests that many dietary natural products are potential sources for prevention and treatment of liver cancer, such as grapes, black currant, plum, pomegranate, cruciferous vegetables, French beans, tomatoes, asparagus, garlic, turmeric, ginger, soy, rice bran, and some edible macro-fungi. These dietary natural products and their active components could affect the development and progression of liver cancer in various ways, such as inhibiting tumor cell growth and metastasis, protecting against liver carcinogens, immunomodulating and enhancing effects of chemotherapeutic drugs. This review summarizes the potential prevention and treatment activities of dietary natural products and their major bioactive constituents on liver cancer, and discusses possible mechanisms of action. PMID:26978396

  15. Plant extracts as natural antioxidants in meat and meat products.

    Science.gov (United States)

    Shah, Manzoor Ahmad; Bosco, Sowriappan John Don; Mir, Shabir Ahmad

    2014-09-01

    Antioxidants are used to minimize the oxidative changes in meat and meat products. Oxidative changes may have negative effects on the quality of meat and meat products, causing changes in their sensory and nutritional properties. Although synthetic antioxidants have already been used but in recent years, the demand for natural antioxidants has been increased mainly because of adverse effects of synthetic antioxidants. Thus most of the recent investigations have been directed towards the identification of natural antioxidants from various plant sources. Plant extracts have been prepared using different solvents and extraction methods. Grape seed, green tea, pine bark, rosemary, pomegranate, nettle and cinnamon have exhibited similar or better antioxidant properties compared to some synthetic ones. This review provides the recent information on plant extracts used as natural antioxidants in meat and meat products, specifically red meat. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Bioactive natural products from Chinese marine flora and fauna

    Institute of Scientific and Technical Information of China (English)

    Zhen-fang ZHOU; Yue-wei GUO

    2012-01-01

    In recent decades,the pharmaceutical application potential of marine natural products has attracted much interest from both natural product chemists and pharmacologists.Our group has long been engaged in the search for bioactive natural products from Chinese marine flora (such as mangroves and algae) and fauna (including sponges,soft corals,and mollusks),resulting in the isolation and characterization of numerous novel secondary metabolites spanning a wide range of structural classes and various biosynthetic origins.Of particular interest is the fact that many of these compounds show promising biological activities,including cytotoxic,antibacterial,and enzyme inhibitory effects- By describing representative studies,this review presents a comprehensive summary regarding the achievements and progress made by our group in the past decade.Several interesting examples are discussed in detail.

  17. Dietary Natural Products for Prevention and Treatment of Liver Cancer

    Directory of Open Access Journals (Sweden)

    Yue Zhou

    2016-03-01

    Full Text Available Liver cancer is the most common malignancy of the digestive system with high death rate. Accumulating evidences suggests that many dietary natural products are potential sources for prevention and treatment of liver cancer, such as grapes, black currant, plum, pomegranate, cruciferous vegetables, French beans, tomatoes, asparagus, garlic, turmeric, ginger, soy, rice bran, and some edible macro-fungi. These dietary natural products and their active components could affect the development and progression of liver cancer in various ways, such as inhibiting tumor cell growth and metastasis, protecting against liver carcinogens, immunomodulating and enhancing effects of chemotherapeutic drugs. This review summarizes the potential prevention and treatment activities of dietary natural products and their major bioactive constituents on liver cancer, and discusses possible mechanisms of action.

  18. In situ natural product discovery via an artificial marine sponge.

    Directory of Open Access Journals (Sweden)

    James J La Clair

    Full Text Available There is continuing international interest in exploring and developing the therapeutic potential of marine-derived small molecules. Balancing the strategies for ocean based sampling of source organisms versus the potential to endanger fragile ecosystems poses a substantial challenge. In order to mitigate such environmental impacts, we have developed a deployable artificial sponge. This report provides details on its design followed by evidence that it faithfully recapitulates traditional natural product collection protocols. Retrieving this artificial sponge from a tropical ecosystem after deployment for 320 hours afforded three actin-targeting jasplakinolide depsipeptides that had been discovered two decades earlier using traditional sponge specimen collection and isolation procedures. The successful outcome achieved here could reinvigorate marine natural products research, by producing new environmentally innocuous sources of natural products and providing a means to probe the true biosynthetic origins of complex marine-derived scaffolds.

  19. Anti-cancer natural products isolated from chinese medicinal herbs

    Directory of Open Access Journals (Sweden)

    Wu Guosheng

    2011-07-01

    Full Text Available Abstract In recent years, a number of natural products isolated from Chinese herbs have been found to inhibit proliferation, induce apoptosis, suppress angiogenesis, retard metastasis and enhance chemotherapy, exhibiting anti-cancer potential both in vitro and in vivo. This article summarizes recent advances in in vitro and in vivo research on the anti-cancer effects and related mechanisms of some promising natural products. These natural products are also reviewed for their therapeutic potentials, including flavonoids (gambogic acid, curcumin, wogonin and silibinin, alkaloids (berberine, terpenes (artemisinin, β-elemene, oridonin, triptolide, and ursolic acid, quinones (shikonin and emodin and saponins (ginsenoside Rg3, which are isolated from Chinese medicinal herbs. In particular, the discovery of the new use of artemisinin derivatives as excellent anti-cancer drugs is also reviewed.

  20. Knowledge based decision making: perspective on natural gas production

    Energy Technology Data Exchange (ETDEWEB)

    Ydstie, B. Erik; Stuland, Kjetil M.

    2009-07-01

    Conclusions (drawn by the author): Decarbonization of energy sources - From coal to renewable. Natural Gas Abundantly available - Norway is no. 3 exporter. Natural gas important as - Hydrogen source for chemicals; - Electricity; - End consumer usage (heating etc). Large potential for application of model based decision making; - Where and when to install platforms and drill wells - How to operate platforms and pipeline systems; - How to operate and optimize chemical production; - Optimization of electricity generation systems. (author)

  1. Marine actinobacteria: an important source of bioactive natural products.

    Science.gov (United States)

    Manivasagan, Panchanathan; Kang, Kyong-Hwa; Sivakumar, Kannan; Li-Chan, Eunice C Y; Oh, Hyun-Myung; Kim, Se-Kwon

    2014-07-01

    Marine environment is largely an untapped source for deriving actinobacteria, having potential to produce novel, bioactive natural products. Actinobacteria are the prolific producers of pharmaceutically active secondary metabolites, accounting for about 70% of the naturally derived compounds that are currently in clinical use. Among the various actinobacterial genera, Actinomadura, Actinoplanes, Amycolatopsis, Marinispora, Micromonospora, Nocardiopsis, Saccharopolyspora, Salinispora, Streptomyces and Verrucosispora are the major potential producers of commercially important bioactive natural products. In this respect, Streptomyces ranks first with a large number of bioactive natural products. Marine actinobacteria are unique enhancing quite different biological properties including antimicrobial, anticancer, antiviral, insecticidal and enzyme inhibitory activities. They have attracted global in the last ten years for their ability to produce pharmaceutically active compounds. In this review, we have focused attention on the bioactive natural products isolated from marine actinobacteria, possessing unique chemical structures that may form the basis for synthesis of novel drugs that could be used to combat resistant pathogenic microorganisms. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Marine Natural Products as Models to Circumvent Multidrug Resistance.

    Science.gov (United States)

    Long, Solida; Sousa, Emília; Kijjoa, Anake; Pinto, Madalena M M

    2016-07-08

    Multidrug resistance (MDR) to anticancer drugs is a serious health problem that in many cases leads to cancer treatment failure. The ATP binding cassette (ABC) transporter P-glycoprotein (P-gp), which leads to premature efflux of drugs from cancer cells, is often responsible for MDR. On the other hand, a strategy to search for modulators from natural products to overcome MDR had been in place during the last decades. However, Nature limits the amount of some natural products, which has led to the development of synthetic strategies to increase their availability. This review summarizes the research findings on marine natural products and derivatives, mainly alkaloids, polyoxygenated sterols, polyketides, terpenoids, diketopiperazines, and peptides, with P-gp inhibitory activity highlighting the established structure-activity relationships. The synthetic pathways for the total synthesis of the most promising members and analogs are also presented. It is expected that the data gathered during the last decades concerning their synthesis and MDR-inhibiting activities will help medicinal chemists develop potential drug candidates using marine natural products as models which can deliver new ABC transporter inhibitor scaffolds.

  3. The impact of natural products upon modern drug discovery.

    Science.gov (United States)

    Ganesan, A

    2008-06-01

    In the period 1970-2006, a total of 24 unique natural products were discovered that led to an approved drug. We analyze these successful leads in terms of drug-like properties, and show that they can be divided into two equal subsets. The first falls in the 'Lipinski universe' and complies with the Rule of Five. The second is a 'parallel universe' that violates the rules. Nevertheless, the latter compounds remain largely compliant in terms of logP and H-bond donors, highlighting the importance of these two metrics in predicting bioavailability. Natural products are often cited as an exception to Lipinski's rules. We believe this is because nature has learned to maintain low hydrophobicity and intermolecular H-bond donating potential when it needs to make biologically active compounds with high molecular weight and large numbers of rotatable bonds. In addition, natural products are more likely than purely synthetic compounds to resemble biosynthetic intermediates or endogenous metabolites, and hence take advantage of active transport mechanisms. Interestingly, the natural product leads in the Lipinski and parallel universe had an identical success rate (50%) in delivering an oral drug.

  4. SCHEMES OF GAS PRODUCTION FROM NATURAL GAS HYDRATES

    Institute of Scientific and Technical Information of China (English)

    李淑霞; 陈月明; 杜庆军

    2003-01-01

    Natural gas hydrates are a kind of nonpolluting and high quality energy resources for future, the reserves of which are about twice of the carbon of the current fossil energy (petroleum, natural gas and coal) on the earth. And it will be the most important energy for the 21st century. The energy balance and numerical simulation are applied to study the schemes of the natural gas hydrates production in this paper,and it is considered that both depressurization and thermal stimulation are effective methods for exploiting natural gas hydrates, and that the gas production of the thermal stimulation is higher than that of the depressurization. But thermal stimulation is non-economic because it requires large amounts of energy.Therefore the combination of the two methods is a preferable method for the current development of the natural gas hydrates. The main factors which influence the production of natural gas hydrates are: the temperature of injected water, the injection rate, the initial saturation of the hydrates and the initial temperature of the reservoir which is the most important factor.

  5. Array comparative genomic hybridization analysis of Trichoderma reesei strains with enhanced cellulase production properties

    Directory of Open Access Journals (Sweden)

    Penttilä Merja

    2010-07-01

    Full Text Available Abstract Background Trichoderma reesei is the main industrial producer of cellulases and hemicellulases that are used to depolymerize biomass in a variety of biotechnical applications. Many of the production strains currently in use have been generated by classical mutagenesis. In this study we characterized genomic alterations in high-producing mutants of T. reesei by high-resolution array comparative genomic hybridization (aCGH. Our aim was to obtain genome-wide information which could be utilized for better understanding of the mechanisms underlying efficient cellulase production, and would enable targeted genetic engineering for improved production of proteins in general. Results We carried out an aCGH analysis of four high-producing strains (QM9123, QM9414, NG14 and Rut-C30 using the natural isolate QM6a as a reference. In QM9123 and QM9414 we detected a total of 44 previously undocumented mutation sites including deletions, chromosomal translocation breakpoints and single nucleotide mutations. In NG14 and Rut-C30 we detected 126 mutations of which 17 were new mutations not documented previously. Among these new mutations are the first chromosomal translocation breakpoints identified in NG14 and Rut-C30. We studied the effects of two deletions identified in Rut-C30 (a deletion of 85 kb in the scaffold 15 and a deletion in a gene encoding a transcription factor on cellulase production by constructing knock-out strains in the QM6a background. Neither the 85 kb deletion nor the deletion of the transcription factor affected cellulase production. Conclusions aCGH analysis identified dozens of mutations in each strain analyzed. The resolution was at the level of single nucleotide mutation. High-density aCGH is a powerful tool for genome-wide analysis of organisms with small genomes e.g. fungi, especially in studies where a large set of interesting strains is analyzed.

  6. Natural Organic Matter Removal and Fouling in a Low Pressure Hybrid Membrane Systems

    Directory of Open Access Journals (Sweden)

    Vedat Uyak

    2014-01-01

    Full Text Available The objective of this study was to investigate powdered activated carbon (PAC contribution to natural organic matter (NOM removal by a submerged MF and UF hybrid systems. It was found that filtration of surface waters by a bare MF and UF membranes removed negligible TOC; by contrast, significant amounts of TOC were removed when daily added PAC particles were predeposited on the membrane surfaces. These results support the assumption that the membranes surface properties and PAC layer structure might have considerably influential factor on NOM removal. Moreover, it was concluded that the dominant removal mechanism of hybrid membrane system is adsorption of NOM within PAC layer rather than size exclusion of NOM by both of membrane pores. Transmembrane pressure (TMP increases with PAC membrane systems support the view that PAC adsorption pretreatment will not prevent the development of membrane pressure; on the contrary, PAC particles themselves caused membrane fouling by blocking the entrance of pores of MF and UF membranes. Although all three source waters have similar HPI content, it appears that the PAC interaction with the entrance of membrane pores was responsible for offsetting the NOM fractional effects on membrane fouling for these source waters.

  7. New hybrids between Saccharomyces sensu stricto yeast species found among wine and cider production strains.

    Science.gov (United States)

    Masneuf, I; Hansen, J; Groth, C; Piskur, J; Dubourdieu, D

    1998-10-01

    Two yeast isolates, a wine-making yeast first identified as a Mel+ strain (ex. S. uvarum) and a cider-making yeast, were characterized for their nuclear and mitochondrial genomes. Electrophoretic karyotyping analyses, restriction fragment length polymorphism maps of PCR-amplified MET2 gene fragments, and the sequence analysis of a part of the two MET2 gene alleles found support the notion that these two strains constitute hybrids between Saccharomyces cerevisiae and Saccharomyces bayanus. The two hybrid strains had completely different restriction patterns of mitochondrial DNA as well as different sequences of the OLI1 gene. The sequence of the OLI1 gene from the wine hybrid strain appeared to be the same as that of the S. cerevisiae gene, whereas the OLI1 gene of the cider hybrid strain is equally divergent from both putative parents, S. bayanus and S. cerevisiae. Some fermentative properties were also examined, and one phenotype was found to reflect the hybrid nature of these two strains. The origin and nature of such hybridization events are discussed.

  8. Effect of daily minimum dissolved oxygen concentration on production of channel x blue hybrid catfish

    Science.gov (United States)

    As the channel x blue hybrid catfish is stocked by an increasing number of catfish farmers, it is important to quantify the production response of this fish to pond dissolved oxygen management strategies. The purpose of this study was to quantify the production and water quality responses of the cha...

  9. Comparative cost analysis of hybrid striped bass fingerling production in ponds and tanks

    Science.gov (United States)

    Year-round production of hybrid striped bass (female white bass Morone chrysops×male striped bass M. saxatilis) fingerlings would allow food fish growers to sell their product throughout the year, which would improve the consistency of market supply and cash flow for the farm. However, pond producti...

  10. COCOON PRODUCTION OF THE SILKWORM, Bombyx mori L. (LEPIDOPTERA: BOMBYCIDAE, FED ON LEAVES OF MULBERRY HYBRIDS

    Directory of Open Access Journals (Sweden)

    GERBSON AZEVEDO DE MENDONÇA

    2010-01-01

    Full Text Available Brazil is the fourth cocoon producer in the world. In São Paulo State there are mulberry some hybrids whose productivity are higher than the commonly cultivated varieties. The objective of this study was to evaluate the effect of mulberry hybrids (Morus spp. on the cocoon production of silkworm (Bombyx mori L.. The experiment was conducted at the Unidade Regional de Pesquisa de Gália do Instituto de Zootecnia, SP. The caterpillars were fed on leaves of the hybrids IZ-3/2, IZ-13/6, IZ-15/7, IZ-19/13, IZ-56/4, IZ-57/2, IZ- 40, IZ-64, in a rearing hut at 25 oC ± 3 oC and 75% ± 5% relative humidity. 'Korin' was used as standard. The hybrids affected the duration of the larval period and the weight of the caterpillars, prepupaes and the silk glands as well. There was a reduction in the duration of larval development when the caterpillars had been fed with hybrid IZ-56/4 and the 'Korin' variety. Hybrids IZ-57/2, IZ-56/4 and IZ-15/7 presented the highest cocoon production.

  11. Possible natural hybridization of two morphologically distinct species of Acropora (Cnidaria, Scleractinia in the Pacific: fertilization and larval survival rates.

    Directory of Open Access Journals (Sweden)

    Naoko Isomura

    Full Text Available Natural hybridization of corals in the Indo-Pacific has been considered rather rare. However, field studies have observed many corals with intermediate interspecific or unusual morphologies. Given that the existence of F1 hybrids with intermediate interspecific morphologies has been proven in the Caribbean, hybrids may also inhabit the Indo-Pacific and occur more frequently than expected. In this study, we focused on two morphologically different species, Acropora florida and A. intermedia, and performed crossing experiments at Akajima Island, Japan. Results showed that these species could hybridize in both directions via eggs and sperm, but that fertilization rates significantly differed according to which species provided eggs. These results are similar to those reported from the Caribbean. Although all embryos developed normally to the planular larval stage, the developmental processes of some hybrid embryos were delayed by approximately 1 h compared with conspecific embryos, suggesting that fertilization occurred 1 h later in interspecific crosses than in intraspecific crosses. More successful hybridization could occur under conditions with low numbers of conspecific colonies. Additionally, a comparison of survival rates between hybrid and intraspecific larvae revealed that intra- and interspecific larvae produced from eggs of A. florida survived for significantly longer than those produced from eggs of A. intermedia. Considering these data, under specific conditions, hybrids can be expected to be produced and survive in nature in the Pacific. Furthermore, we identified one colony with intermediate morphology between A. florida and A. intermedia in the field. This colony was fertilized only by eggs of A. florida, with high fertilization rates, suggesting that this colony would be a hybrid of these two species and might be backcrossed.

  12. Patentability potential of natural products for xerostomia treatment

    OpenAIRE

    2016-01-01

    Xerostomia is characterized as a symptom caused by hyposalivation, which can occur for reasons such as age, polypharmacy, radiation therapy, among others. Currently,few products are available for the treatment of xerostomia, which is a subject still underestimated by many health professionals. Thus, we searched patents applied and approved in Brazil on xerostomia, to verify the existing innovation involving natural products. We found 33 patents applied and approved in Brazil, many of them usi...

  13. Electrospun antimicrobial hybrid mats: Innovative packaging material for meat and meat-products.

    Science.gov (United States)

    Amna, Touseef; Yang, Jieun; Ryu, Kyeong-Seon; Hwang, I H

    2015-07-01

    To prevent the development and spread of spoilage/pathogenic microorganisms via meat foodstuffs, antimicrobial nanocomposite packaging can serve as a potential alternative. The objective of this study was to develop a new class of antimicrobial hybrid packaging mat composed of biodegradable polyurethane supplemented with virgin olive oil and zinc oxide via electrospinning. Instead of mixing antimicrobial compounds directly with food, incorporation in packaging materials allows the functional effect at food surfaces where microbial activity is localized. The nanofibers were characterized by SEM, EDX, XRD and TEM. The antibacterial activity was tested against two common foodborne pathogens viz., Staphylococcus aureus and Salmonella typhimurium. The present results indicated that incorporation of olive oil in the polymer affected morphology of PU nanofibers and nanocomposite packaging were able to inhibit growth of pathogens. Thus; as-spun mat can be used as prospective antimicrobial packaging, which potentially reduces contamination of meat/meat-products. Moreover, introduced biodegradable packaging for meat products could serve to replace PVC films and simultaneously help to protect natural environment.

  14. Genus Cebus Q- and G-band karyotypes and natural hybrids.

    Science.gov (United States)

    Torres de Caballero, O M; Ramirez, C; Yunis, E

    1976-01-01

    The Q- and G-band analyses of Cebus capucinus, Cebus albifrons and Cebus apella are presented. The study is based on the results obtained from 18 specimens of the genus. For almost all of them, their exact locality is known. The data presented include the statement of two natural hybrids from C. capucinus and C. albifrons. On an evolutionary basis our results agree with the taxonomic concepts which postulate more similarity between C. capucinus and C. albifrons than between C. capucinus and C. apella. Furthermore, the comparative study of the Q- and G-band patterns indicates an independent chromosome evolution for C. albifrons and C. apella derived from a common ancestor more similar to C. capucinus.

  15. Evaluation of mechanical properties of natural hybrid fibers, reinforced polyester composite materials

    Directory of Open Access Journals (Sweden)

    S. Kasiviswanathan

    2015-12-01

    Full Text Available The composite materials are replacing the traditional materials, because of its superior properties such as high tensile strength, low thermal expansion, high strength to weight ratio. The developments of new materials are on the anvil and are growing day by day. In this work the effect of glass fibre hybridization with the randomly oriented natural fibers has been evaluated. The sisal (S, banana (B, E-glass synthetic fibers were chopped and reinforced with polyester matrix. Six layers were prepared in the following stacking sequence of S/B/G, S/G/B, G/S/B, G/S/B/G/S/B/G, S/G/B//S/G/B, B/G/S/B/G/S. The mechanical properties like impact strength, flexural strength and tensile strength were investigated and compared. It was observed that the addition of two and three layer of glass fiber can improve the mechanical properties like tensile, Flexural and impact strength.

  16. Combustion characteristics of natural gas-hydrogen hybrid fuel turbulent diffusion flame

    Energy Technology Data Exchange (ETDEWEB)

    El-Ghafour, S.A.A.; El-dein, A.H.E.; Aref, A.A.R. [Mechanical Power Engineering Department, Faculty of Engineering, Suez Canal University, Port-Said (Egypt)

    2010-03-15

    Combustion characteristics of natural gas - hydrogen hybrid fuel were investigated experimentally in a free jet turbulent diffusion flame flowing into a slow co-flowing air stream. Experiments were carried out at a constant jet exit Reynolds number of 4000 and with a wide range of NG-H{sub 2} mixture concentrations, varied from 100%NG to 50%NG-50% H{sub 2} by volume. The effect of hydrogen addition on flame stability, flame length, flame structure, exhaust species concentration and pollutant emissions was conducted. Results showed that, hydrogen addition sustains a progressive improvement in flame stability and reduction in flame length, especially for relatively high hydrogen concentrations. Hydrogen-enriched flames found to have a higher combustion temperatures and reactivity than natural gas flame. Also, it was found that hydrogen addition to natural gas is an ineffective strategy for NO and CO reduction in the studied range, while a significant reduction in the %CO{sub 2} molar concentration by about 30% was achieved. (author)

  17. Hybrid life-cycle assessment of natural gas based fuel chains for transportation.

    Science.gov (United States)

    Strømman, Anders Hammer; Solli, Christian; Hertwich, Edgar G

    2006-04-15

    This research compares the use of natural gas, methanol, and hydrogen as transportation fuels. These three fuel chains start with the extraction and processing of natural gas in the Norwegian North Sea and end with final use in Central Europe. The end use is passenger transportation with a sub-compact car that has an internal combustion engine for the natural gas case and a fuel cell for the methanol and hydrogen cases. The life cycle assessment is performed by combining a process based life-cycle inventory with economic input-output data. The analysis shows that the potential climate impacts are lowest for the hydrogen fuel scenario with CO2 deposition. The hydrogen fuel chain scenario has no significant environmental disadvantage compared to the other fuel chains. Detailed analysis shows that the construction of the car contributes significantly to most impact categories. Finally, it is shown how the application of a hybrid inventory model ensures a more complete inventory description compared to standard process-based life-cycle assessment. This is particularly significant for car construction which would have been significantly underestimated in this study using standard process life-cycle assessment alone.

  18. Idaho Habitat and Natural Production Monitoring : Annual Report 1989.

    Energy Technology Data Exchange (ETDEWEB)

    Kiefer, Russell B.; Forster, Katharine A.

    1991-01-01

    Project 83-7 was established under the Northwest Power Planning Council's 1982 Fish and Wildlife Program to monitor natural production of anadromous fish, evaluate Bonneville Power Administration (BPA) habitat improvement projects, and develop a credit record for off-site mitigation projects in Idaho. Project 83-7 is divided into two subprojects: general and intensive monitoring. Primary objectives of the general monitoring subproject (Part 1) are to determine natural production increases due to habitat improvement projects in terms of parr production and to determine natural production status and trends in Idaho. The second objective is accomplished by combining parr density data from monitoring and evaluation of BPA habitat projects and from other Idaho Department of Fish and Game (IDFG) management and research activities. Primary objectives of the intensive monitoring subproject (Part 2) are to determine the number of returning chinook and steelhead adults necessary to achieve optimal smolt production and to develop mitigation accounting based on increases in smolt production. Two locations are being intensively studied to meet these objectives. Field work began in 1987 in the upper Salmon River and Crooked River (South Fork Clearwater River tributary). 22 refs., 10 figs., 17 tabs.

  19. Pseudomonas putida—a versatile host for the production of natural products

    OpenAIRE

    Loeschcke, Anita; Thies, Stephan

    2015-01-01

    The biosynthesis of natural products by heterologous expression of biosynthetic pathways in amenable production strains enables biotechnological access to a variety of valuable compounds by conversion of renewable resources. Pseudomonas putida has emerged as a microbial laboratory work horse, with elaborated techniques for cultivation and genetic manipulation available. Beyond that, this bacterium offers several particular advantages with regard to natural product biosynthesis, notably a vers...

  20. The EROI of Conventional Canadian Natural Gas Production

    Directory of Open Access Journals (Sweden)

    Jon Freise

    2011-11-01

    Full Text Available Canada was the world’s third largest natural gas producer in 2008, with 98% of its gas being produced by conventional, tight gas, and coal bed methane wells in Western Canada. Natural gas production in Western Canada peaked in 2001 and remained nearly flat until 2006 despite more than quadrupling the drilling rate. Canada seems to be one of many counter examples to the idea that oil and gas production can rise with sufficient investment. This study calculated the Energy Return on Energy Invested and Net Energy of conventional natural gas and oil production in Western Canada by a variety of methods to explore the energy dynamics of the peaking process. All these methods show a downward trend in EROI during the last decade. Natural gas EROI fell from 38:1 in 1993 to 15:1 at the peak of drilling in 2005. The drilling intensity for natural gas was so high that net energy delivered to society peaked in 2000–2002, while production did not peak until 2006. The industry consumed all the extra energy it delivered to maintain the high drilling effort. The inability of a region to increase net energy may be the best definition of peak production. This increase in energy consumption reduces the total energy provided to society and acts as a contracting pressure on the overall economy as the industry consumes greater quantities of labor, steel, concrete and fuel. It appears that energy production from conventional oil and gas in Western Canada has peaked and entered permanent decline.

  1. Natural products as storage media for avulsed tooth

    Directory of Open Access Journals (Sweden)

    Deepika Jain

    2015-01-01

    Full Text Available Avulsion of tooth is complete displacement of tooth out of its socket that results in mutilation of periodontal ligaments. The desirable treatment option is replantation of the tooth. However, unsuccessful replantation is a matter of great discontentment. Unsuccessful replantation is due to inappropriate management of the avulsed tooth. Protection of teeth from desiccation due to drying of the periodontal ligament tissue, by keeping it in storage media can improve the outcome of the treatment. This review paper focuses on the use of natural products as storage media for avulsed teeth. In vitro and in vivo research published during 1995-2014, allowing open access on National Center for Biotechnology Information (NCBI database and articles on EBSCO host (EBSCO-Elton B. Stephens Company were included. It was found that natural products such as milk, coconut water, propolis, green tea, red mulberry, Aloe vera, egg-white and pomegranate have shown ability to maintain viability of periodontal ligament cells of avulsed teeth. Few natural products such as coconut water and milk can be used in raw form, while other products such as green tea and red mulberry need processing. Ability to maintain periodontal cell viability for a longer time is warranted in cases of major accidents, where teeth can be replanted only after other major surgeries. Natural products have easy availability, greater efficacy and longer storage time as compared to Hank′s balanced salt solution which has been recommended by the International Association of Dental Traumatology as standard solution for storage of avulsed teeth. Natural products have shown good qualities in in vitro experiments; further in vivo studies are needed to evaluate their efficacy as storage media.

  2. Production of hydrogen by thermocatalytic cracking of natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Muradov, N.Z. [Univ. of Central Florida, Cape Canaveral, FL (United States)

    1995-09-01

    It is universally accepted that in the next few decades hydrogen production will continue to rely on fossil fuels (primarily, natural gas). On the other hand, the conventional methods of hydrogen production from natural gas (for example, steam reforming) are complex multi-step processes. These processes also result in the emission of large quantities of CO{sub 2} into the atmosphere that produce adverse ecological effects. One alternative is the one-step thermocatalytic cracking (TCC) (or decomposition) of natural gas into hydrogen and carbon. Preliminary analysis indicates that the cost of hydrogen produced by thermal decomposition of natural gas is somewhat lower than the conventional processes after by-product carbon credit is taken. In the short term, this process can be used for on-site production of hydrogen-methane mixtures in gas-filling stations and for CO{sub x}-free production of hydrogen for fuel cell driven prime movers. The experimental data on the thermocatalytic cracking of methane over various catalysts and supports in a wide range of temperatures (500-900{degrees}C) are presented in this paper. Two types of reactors were designed and built at FSEC: continuous flow and pulse fix bed catalytic reactors. The temperature dependence of the hydrogen production yield using oxide type catalysts was studied. Alumina-supported Ni- and Fe-catalysts demonstrated relatively high efficiency in the methane cracking reaction at moderate temperatures (600-800{degrees}C). Kinetic curves of hydrogen production over metal and metal oxide catalysts at different temperatures are presented in the paper. Fe-catalyst demonstrated good stability (for several hours), whereas alumina-supported Pt-catalyst rapidly lost its catalytic activity.

  3. The catalytic conversion of natural gas to useful products

    NARCIS (Netherlands)

    Ross, J.R.H.; Ross, J.R.H.; van Keulen, A.N.J.; van Keulen, A.N.J.; Hegarty, M.E.S.; Seshan, Kulathuiyer

    1996-01-01

    This paper gives a brief summary of some processes, direct and indirect, for the conversion of natural gas to useful products. It then proceeds to give an outline of some work from the authors' laboratories on subjects such as steam reforming, oxidative coupling and CO2 reforming of methane, paying

  4. Liquefied natural gas production at Hammerfest: A transforming marine community

    NARCIS (Netherlands)

    Bets, van L.K.J.; Tatenhove, van J.P.M.; Mol, A.P.J.

    2016-01-01

    Global energy demand and scarce petroleum resources require communities to adapt to a rapidly changing Arctic environment, but as well to a transforming socio-economic environment instigated by oil and gas development. This is illustrated by liquefied natural gas production by Statoil at Hammerfest,

  5. The 9th European Conference on Marine Natural Products

    Directory of Open Access Journals (Sweden)

    RuAngelie Edrada-Ebel

    2015-12-01

    Full Text Available The 9th European Conference on Marine Natural Products (ECMNP in Glasgow follows its predecessors in La Toja (2013, Tjärnö (2011, Porto (2009, Ischia (2007, Paris (2005, Elmau (2002, Santiago de Compostela (1999, and Athens (1997. [...

  6. Bioactive Natural Products From Chinese Tropical Marine Organisms

    Institute of Scientific and Technical Information of China (English)

    GUO,Yue-Wei

    2004-01-01

    @@ The oceans contain a vast biological diversity of species that have so far been utilized by mankind mainly as a source of protein. In the last few decades, however, natural products chemists have started to discover the wealth of bioactive secondary metabolites that are produced by marine invertebrates such as sponges, soft corals, molluscs and others.

  7. Expedient total synthesis of pyrrothine natural products and analogs

    DEFF Research Database (Denmark)

    Hjelmgaard, Thomas; Givskov, Michael Christian; Nielsen, John

    2007-01-01

    This paper describes an expedient and straightforward total synthesis of the two pyrrothine natural products holomycin (7 steps, 11% overall) and xenorhabdin I (7 steps, 11% overall) and analogs thereof via a common late-stage intermediate. The pathway proceeds via the pyrrothine hydrochloride...

  8. Current perspectives in drug discovery against tuberculosis from natural products.

    Science.gov (United States)

    Nguta, Joseph Mwanzia; Appiah-Opong, Regina; Nyarko, Alexander K; Yeboah-Manu, Dorothy; Addo, Phyllis G A

    2015-09-01

    Currently, one third of the world's population is latently infected with Mycobacterium tuberculosis (MTB), while 8.9-9.9 million new and relapse cases of tuberculosis (TB) are reported yearly. The renewed research interests in natural products in the hope of discovering new and novel antitubercular leads have been driven partly by the increased incidence of multidrug-resistant strains of MTB and the adverse effects associated with the first- and second-line antitubercular drugs. Natural products have been, and will continue to be a rich source of new drugs against many diseases. The depth and breadth of therapeutic agents that have their origins in the secondary metabolites produced by living organisms cannot be compared with any other source of therapeutic agents. Discovery of new chemical molecules against active and latent TB from natural products requires an interdisciplinary approach, which is a major challenge facing scientists in this field. In order to overcome this challenge, cutting edge techniques in mycobacteriology and innovative natural product chemistry tools need to be developed and used in tandem. The present review provides a cross-linkage to the most recent literature in both fields and their potential to impact the early phase of drug discovery against TB if seamlessly combined.

  9. Low Carbon Technology Options for the Natural Gas Electricity Production

    Science.gov (United States)

    The ultimate goal of this task is to perform environmental and economic analysis of natural gas based power production technologies (different routes) to investigate and evaluate strategies for reducing emissions from the power sector. It is a broad research area. Initially, the...

  10. Solvent-free extraction of food and natural products

    OpenAIRE

    Fabiano-Tixier, Anne-Sylvie; Vian, Maryline; Allaf, Tamara; Vorobiev, Eugene

    2015-01-01

    This review presents useful and green techniques of solvent-free extraction used in ancient times, such as extraction of olive oil and citrus essential oil, and innovative techniques, such as pulsed electric field, microwave, instantaneous controlled pressure drop, and extrusion. We discuss the devices, their applications, mechanisms, and parameters influencing sample preparation prior to analysis of natural products.

  11. Low Carbon Technology Options for the Natural Gas Electricity Production

    Science.gov (United States)

    The ultimate goal of this task is to perform environmental and economic analysis of natural gas based power production technologies (different routes) to investigate and evaluate strategies for reducing emissions from the power sector. It is a broad research area. Initially, the...

  12. A New Golden Age of Natural Products Drug Discovery

    Science.gov (United States)

    Shen, Ben

    2016-01-01

    The 2015 Nobel Prize in Physiology or Medicine has been awarded to William C. Campbell and Satoshi Omura, and Youyou Tu for the discovery of avermectins and artemisinin, respectively, therapies that revolutionized the treatment of devastating parasite diseases. With the recent technological advances, a New Golden Age of natural products drug discovery is dawning. PMID:26638061

  13. Natural products chemistry research 2010's progress in China.

    Science.gov (United States)

    Ye, Yang; Li, Xi-Qiang; Tang, Chun-Ping; Yao, Sheng

    2012-01-01

    This article reviews the progresses made by Chinese scientists in the field of natural products chemistry in 2010. Selected compounds with unique structural features and/or promising bioactivities were described herein on the basis of structural types. Copyright © 2012 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  14. Stereoselective Total Synthesis of Bioactive Marine Natural Product Biselyngbyolide B.

    Science.gov (United States)

    Das, Sayantan; Paul, Debobrata; Goswami, Rajib Kumar

    2016-04-15

    A convergent strategy for the stereoselective total synthesis of biologically active marine natural product biselyngbyolide B has been developed. Key strategies of this synthesis include Jamison protocol of trans-hydroalumination/allylation for installation of C18-C23 olefin moiety and intramolecular Heck coupling for macrocyclization.

  15. Natural Products as Source of Therapeutics against Parasitic Diseases.

    Science.gov (United States)

    Hertweck, Christian

    2015-12-01

    An end to suffering: Parasitic infections with protozoa and worms cause unimaginable misery, in particular in the tropics. Fortunately, natural products, such as the antimalarial artemisinin (1) and the anthelmintic avermectin (2) were discovered and developed into therapeutics. These major achievements now culminated in the 2015 Nobel Prize for Medicine.

  16. Short history of natural product research in the CSIR

    CSIR Research Space (South Africa)

    Walwyn, D

    2006-02-01

    Full Text Available Natural product research has been a major component of the CSIR's bioscience activities for its entire history, and particularly in the 1960s and 1970s. This type of work is also strongly aligned with one of the objectives of the CSIR, namely...

  17. The effect of fibre layering pattern in resisting bending loads of natural fibre-based hybrid composite materials

    Directory of Open Access Journals (Sweden)

    Jusoh Muhamad Shahirul Mat

    2016-01-01

    Full Text Available The effect of fibre layering pattern and hybridization on the flexural properties of composite hybrid laminates between natural fibres of basalt, jute and flax with synthetic fibre of E-glass reinforced epoxy have been investigated experimentally. Results showed that the effect fibre layering pattern was highly significant on the flexural strength and modulus, which were strongly dependent on the hybrid configuration between sandwich-like (SL and intercalation (IC sequence of fibre layers. In addition, specific modulus based on the variation densities of the hybrid laminates was used to discover the best combination either basalt, jute or flax with E-glass exhibits superior properties concerning on the strength to weight-ratio. Generally, SL sequence of glass/basalt exhibited superior strength and stiffness compared with glass/jute and glass/flax in resisting bending loads. In terms of hybridization effect, glass/jute was found to be the best combination with E-glass compared to the rest of natural fibres investigated in the present study. Hence, the proper stacking sequences and material selection are among predominant factors that influence on mechanical properties and very crucial in designing composite hybrid system to meet the desired requirements.

  18. Natural product derived insecticides: discovery and development of spinetoram.

    Science.gov (United States)

    Galm, Ute; Sparks, Thomas C

    2016-03-01

    This review highlights the importance of natural product research and industrial microbiology for product development in the agricultural industry, based on examples from Dow AgroSciences. It provides an overview of the discovery and development of spinetoram, a semisynthetic insecticide derived by a combination of a genetic block in a specific O-methylation of the rhamnose moiety of spinosad coupled with neural network-based QSAR and synthetic chemistry. It also emphasizes the key role that new technologies and multidisciplinary approaches play in the development of current spinetoram production strains.

  19. Marine Natural Products as Lead Compound for New Drug Discovery

    Institute of Scientific and Technical Information of China (English)

    JIANG; Biao

    2001-01-01

    The study of natural product has long been motivated by a quest for some benefit to man, the discover. Recent years have witnessed growing attention to the isolation, identification and synthesis of the marine natural. Although marine organisms do not have a long history of medicine applications like terrestrial plants, some marine organisms have left an extensive record of hazard to mankind. The isolation and identification of saxtoxin, tetradotoxin and lyngbyatoxin resulted from such reported. The marine biosphere has long held great promise as source of anticancer compounds, while a number of screening efforts has indicated a much higher percentage of antineplastic and antitumor activity than terrestrial plants. Several marine natural products have made their appearance in clinical trials at the National Cancer Institute, such as the didemnis, , bryostatins, This finds marine invertebratehave reinvigorated interest and effort in anticancer agent from marine invertebrate.  ……

  20. Marine Natural Products as Lead Compound for New Drug Discovery

    Institute of Scientific and Technical Information of China (English)

    JIANG Biao

    2001-01-01

    @@ The study of natural product has long been motivated by a quest for some benefit to man, the discover. Recent years have witnessed growing attention to the isolation, identification and synthesis of the marine natural. Although marine organisms do not have a long history of medicine applications like terrestrial plants, some marine organisms have left an extensive record of hazard to mankind. The isolation and identification of saxtoxin, tetradotoxin and lyngbyatoxin resulted from such reported. The marine biosphere has long held great promise as source of anticancer compounds, while a number of screening efforts has indicated a much higher percentage of antineplastic and antitumor activity than terrestrial plants. Several marine natural products have made their appearance in clinical trials at the National Cancer Institute, such as the didemnis, , bryostatins, This finds marine invertebratehave reinvigorated interest and effort in anticancer agent from marine invertebrate.

  1. Synthesis of psymberin analogues: probing a functional correlation with the pederin/mycalamide family of natural products.

    Science.gov (United States)

    Jiang, Xin; Williams, Noelle; De Brabander, Jef K

    2007-01-18

    In this letter we describe an efficient synthesis of "psympederin", a hybrid between the novel antitumor natural product psymberin and the blister beetle toxin pederin. Evaluation of antiproliferative activity reveals that the dihydroisocoumarin fragment is important for psymberin toxicity and the cyclic pederate fragment is important for pederin/mycalamide toxicity. On the basis of preliminary results described herein, we speculate that, despite their structural resemblance, psymberin and pederin/mycalamide induce toxicity through different mechanisms. [reaction: see text].

  2. HEURISTIC OPTIMIZATION OF NATURAL PRODUCTION INVENTORY MODELS WITH THE PREFERENCE OF A DECISION MAKER

    OpenAIRE

    CHIH HSUN HSIEH

    2008-01-01

    In this paper, two natural production inventory models based on fuzzy total production inventory cost with the preference of a decision maker are introduced, and combined by natural number parameters in which values are linguistic values in natural language, crisp real number variables, and fuzzy number variables. These are the one natural production inventory model for crisp production quantity, and the other natural production inventory model for fuzzy production quantity. The natural arith...

  3. 16th International Conference on Hybrid Intelligent Systems and the 8th World Congress on Nature and Biologically Inspired Computing

    CERN Document Server

    Haqiq, Abdelkrim; Alimi, Adel; Mezzour, Ghita; Rokbani, Nizar; Muda, Azah

    2017-01-01

    This book presents the latest research in hybrid intelligent systems. It includes 57 carefully selected papers from the 16th International Conference on Hybrid Intelligent Systems (HIS 2016) and the 8th World Congress on Nature and Biologically Inspired Computing (NaBIC 2016), held on November 21–23, 2016 in Marrakech, Morocco. HIS - NaBIC 2016 was jointly organized by the Machine Intelligence Research Labs (MIR Labs), USA; Hassan 1st University, Settat, Morocco and University of Sfax, Tunisia. Hybridization of intelligent systems is a promising research field in modern artificial/computational intelligence and is concerned with the development of the next generation of intelligent systems. The conference’s main aim is to inspire further exploration of the intriguing potential of hybrid intelligent systems and bio-inspired computing. As such, the book is a valuable resource for practicing engineers /scientists and researchers working in the field of computational intelligence and artificial intelligence.

  4. Systematics-guided bioprospecting for bioactive microbial natural products.

    Science.gov (United States)

    Liu, Xueting; Bolla, Krishna; Ashforth, Elizabeth Jane; Zhuo, Ying; Gao, Hong; Huang, Pei; Stanley, Sarah A; Hung, Deborah T; Zhang, Lixin

    2012-01-01

    Advances in the taxonomic characterization of microorganisms have accelerated the rate at which new producers of natural products can be understood in relation to known organisms. Yet for many reasons, chemical efforts to characterize new compounds from new microbes have not kept pace with taxonomic advances. That there exists an ever-widening gap between the biological versus chemical characterization of new microorganisms creates tremendous opportunity for the discovery of novel natural products through the calculated selection and study of organisms from unique, untapped, ecological niches. A systematics-guided bioprospecting, including the construction of high quality libraries of marine microbes and their crude extracts, investigation of bioactive compounds, and increasing the active compounds by precision engineering, has become an efficient approach to drive drug leads discovery. This review outlines the recent advances in these issues and shares our experiences on anti-infectious drug discovery and improvement of avermectins production as well.

  5. Synthetic biology tools for bioprospecting of natural products in eukaryotes.

    Science.gov (United States)

    Unkles, Shiela E; Valiante, Vito; Mattern, Derek J; Brakhage, Axel A

    2014-04-24

    Filamentous fungi have the capacity to produce a battery of natural products of often unknown function, synthesized by complex metabolic pathways. Unfortunately, most of these pathways appear silent, many in intractable organisms, and their products consequently unidentified. One basic challenge is the difficulty of expressing a biosynthesis pathway for a complex natural product in a heterologous eukaryotic host. Here, we provide a proof-of concept solution to this challenge and describe how the entire penicillin biosynthesis pathway can be expressed in a heterologous host. The method takes advantage of a combination of improved yeast in vivo cloning technology, generation of polycistronic mRNA for the gene cluster under study, and an amenable and easily manipulated fungal host, i.e., Aspergillus nidulans. We achieve expression from a single promoter of the pathway genes to yield a large polycistronic mRNA by using viral 2A peptide sequences to direct successful cotranslational cleavage of pathway enzymes.

  6. Natural products - plenty more where that came from

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, M.

    1980-12-22

    In this article, natural products and their possible use as renewable resources are reviewed. The fermentation of corn for the production of alcohol for motor fuel is discussed and other crops for this purpose include sugar cane, cassava, sweet potato and Jerusalem artichoke. The hydrolysis of cellulose to sugars based on enzyme hydrolysis is currently being researched in the USA. Also in the USA, Melvin Calvin hopes to breed a rubber-bearing plant whose latex can be easily cracked to motor fuel. Guayule and jojoba rubber-bearing plants are also the focus of research at present. The importance of natural vegetation in the manufacturing of medicines and in the chemical and food industries is stressed. Finally products of the sea, particularly alginates and carragheenins are mentioned, but as yet, the full potential of the sea to yield renewable resources is unknown.

  7. Virtual Natural Product Library - full text searchable database

    Directory of Open Access Journals (Sweden)

    Subhash Chandra Bose. Kotte

    2012-05-01

    Full Text Available Small molecules occurring in nature have special significance to mankind. They have varied applications from healthcare, food, nutrition, agriculture, personal care and well-being. These natural small molecules are from very diverse sources from the rarest plants to deep sea creatures. Recently they have assumed a lot of significance as pharmaceutical companies is constantly pushing the horizons to make them druggable due to their inherent bioactivities. Though they are not easy to synthesize or isolate, yet their diverse molecular scaffold confers them significance especially given the fact of prevailing resistance to drug scaffolds presently being used in the clinics. Hence its of paramount importance to have a database of diverse natural small molecules through the present effort of creating a Virtual Natural Products Library (VNPL-version 0.15.

  8. Infrared Spectroscopy Study of Structural Nature of Geopolymeric Products

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yunsheng; SUN Wei; LI Zongjin

    2008-01-01

    The bonding status and chemical environment of SiO4 and AlO4 tetrahedras of three types of geopolymeric products were systematically investigated by infrared spectroscopy.The relationship between amorphous geopolymeric products and zeolite crystals with the same overall chemical compositions was also discussed.The infrared evidence shows that SiO4 tetrahedra is partially bonded by AlO4 during the hydration process ofgeopolymeric cement.The two types of tetrahedras jointly construct the three dimensional framework structures of the geopolymeric products.The mutual transformation between geopolymeric products and corresponding zeolite crystals will take place once the reaction condition is suitable,which reveals that the nature ofgeopolymeric products are probably the amorphous equivalent of the corresponding zeolite crystals.

  9. The hybrid front end PCBs production for the CMS preshower

    CERN Document Server

    Soukoulias, P

    2009-01-01

    The High Energy Physics Detector CMS (Compact Muon Solenoid),installed at the Large Hadron Collider(LHC) at CERN,Geneva,has been built by an International Collaboration;CMS will measure and identify the particles from proton-proton collisions.One of the CMS component is the Preshower sub-detector,comprising 5000 silicon strip sensors connected to Hybrid Front End Boards for the readout.This paper focuses on an in-kind contibution of Greece.This work was carried out by researches,engineers and managers from a medium size Company,Prisma Electronics,located in Alexandropolis and researchers from CERN in Geneva,Demokritos in Athens and the University of Ioannina.The number of pieces fitting the technical specifications was close to 100%.Because of that,in March 2009,Prisma received as recognition a CERN CMS gold award.

  10. Field tests of a natural vacuum solar desalination system using hybrid solar collector

    Science.gov (United States)

    Setyawan, Eko Y.; Napitupulu, Richard A. M.; Siagian, Parulian; Ambarita, Himsar

    2017-09-01

    This study deals with field test of a natural vacuum solar desalination system using hybrid type solar collector. In order to perform the tests, a natural vacuum solar desalination has been designed and fabricated. The dimension of evaporator is 1000 mm ×1000 mm × 200 mm, while dimension of solar collector is 1000 mm ×1500 mm. The system is tested by exposing to solar radiation in Medan city of Indonesia for five days. The solar radiations during test are 8.79 MJ/m2, 10.14 MJ/m2, 6.88 MJ/m2, 11.05 MJ/m2, and 11.36 MJ/m2, respectively. The produced fresh waters are 160 ml, 180 ml, 118 ml, 206 ml, 220 ml, respectively. The conclusions are as follows. The produced fresh water is still very low due to the heat from the solar collector is not transferred perfectly to the evaporator. There produced fresh water is strongly affected by solar irradiation. It is recommended to minimize the heat loss from the evaporator and the transfer fluid.

  11. Natural-Synthetic Hybrid Polymers Developed via Electrospinning: The Effect of PET in Chitosan/Starch System

    Directory of Open Access Journals (Sweden)

    Carlos Velasco-Santos

    2011-03-01

    Full Text Available Chitosan is an amino polysaccharide found in nature, which is biodegradable, nontoxic and biocompatible. It has versatile features and can be used in a variety of applications including films, packaging, and also in medical surgery. Recently a possibility to diversify chitosan properties has emerged by combining it with synthetic materials to produce novel natural-synthetic hybrid polymers. We have studied structural and thermophysical properties of chitosan + starch + poly(ethylene terephthalate (Ch + S + PET fibers developed via electrospinning. Properties of these hybrids polymers are compared with extant chitosan containing hybrids synthesized by electrospinning. Molecular interactions and orientation in the fibers are analyzed by infrared and Raman spectroscopies respectively, morphology by scanning electron microscopy and thermophysical properties by thermogravimetric analysis and differential scanning calorimetry. Addition of PET to Ch + S systems results in improved thermal stability at elevated temperatures.

  12. Natural-synthetic hybrid polymers developed via electrospinning: the effect of PET in chitosan/starch system.

    Science.gov (United States)

    Espíndola-González, Adolfo; Martínez-Hernández, Ana Laura; Fernández-Escobar, Francisco; Castaño, Victor Manuel; Brostow, Witold; Datashvili, Tea; Velasco-Santos, Carlos

    2011-01-01

    Chitosan is an amino polysaccharide found in nature, which is biodegradable, nontoxic and biocompatible. It has versatile features and can be used in a variety of applications including films, packaging, and also in medical surgery. Recently a possibility to diversify chitosan properties has emerged by combining it with synthetic materials to produce novel natural-synthetic hybrid polymers. We have studied structural and thermophysical properties of chitosan + starch + poly(ethylene terephthalate) (Ch + S + PET) fibers developed via electrospinning. Properties of these hybrids polymers are compared with extant chitosan containing hybrids synthesized by electrospinning. Molecular interactions and orientation in the fibers are analyzed by infrared and Raman spectroscopies respectively, morphology by scanning electron microscopy and thermophysical properties by thermogravimetric analysis and differential scanning calorimetry. Addition of PET to Ch + S systems results in improved thermal stability at elevated temperatures.

  13. [Interspecific hybridization in the genus Paeonia (Paeoniaceae): polymorphic sites in transcribed spacers of the 45S rRNA genes as indicators of natural and artificial peony hybrids].

    Science.gov (United States)

    Punina, E O; Machs, E M; Krapivskaia, E E; Kim, E S; Mordak, E V; Miakoshina, Iu A; Rodionov, A V

    2012-07-01

    The ITS1-5.8S rDNA-ITS2 regions of 33 accessions belonging to 16 species and five natural and garden interspecific hybrids of the genus Paeonia L. were sequenced. Chromatograms of the peony hybrids demonstrated the presence of the signals, corresponding to two different nucleotides at the positions differing in the parents, indicating that in the hybrids, no rDNA isogenization usually occurred, and they preserved rDNA of both parents. Analysis of these polymorphic sites (PS) showed that P. x majkoae was interspecific hybrid between P. tenuifolia and P. caucasica. The ITS of P. hybrida differs from ITS of P. x majkoae in 19 mutations. Because of this, P. x majkoae is definitely not synonymous to P. hybrida. Comparative analysis of ITS 1-5.8S rDNA-ITS2 showed that species diversity in section Paeonia was based on recombination as a result of intraspecific hybridization of three haplotype families. Specifically, haplotypes A, typical of the P. tenuifolia and P. anomala genomes, haplotypes B, typical of P. mlokosewitschii and P. obovata, and haplotypes of family C, currently represented in rDNA of diploid and tetraploid forms of some Caucasian and Mediterranean species. The ITS regions many diploid peonies contain no dimorphic sites, while P. oreogeton, P. cambessedesii, P. rhodia, and P. daurica carry from ten to 17 PS, and supposed to be the interspecific hybrids. Most of the tetraploid peonies contain from six to 18 PS in the ITS regions. These are alloploids with one of the parental genomes similar to that of P. mlokosewitschii (B1), or P. obovata (B3). The second parental genome in P. banatica, P. peregrina, and P. russii is represented by the genome, close to that of P. tenuifolia (A). P. macrophylla, P. mascula, P. coriacea, P. wittmanniana, and P. tomentosa carry genome of series B and genome of series C, which slightly resembles genome A.

  14. Interdisciplinary researches for potential developments of drugs and natural products

    Directory of Open Access Journals (Sweden)

    Arunrat Chaveerach

    2017-04-01

    Full Text Available Developments of drugs or natural products from plants are possibly made, simple to use and lower cost than modern drugs. The development processes can be started with studying local wisdom and literature reviews to choose the plants which have long been used in diverse areas, such as foods, traditional medicine, fragrances and seasonings. Then those data will be associated with scientific researches, namely plant collection and identification, phytochemical screening by gas chromatography-mass spectrometry, pharmacological study/review for their functions, and finally safety and efficiency tests in human. For safety testing, in vitro cell toxicity by cell viability assessment and in vitro testing of DNA breaks by the comet assay in human peripheral blood mononuclear cells can be performed. When active chemicals and functions containing plants were chosen with safety and efficacy for human uses, then, the potential medicinal natural products will be produced. Based on these procedures, the producing cost will be cheaper and the products can be evaluated for their clinical properties. Thus, the best and lowest-priced medicines and natural products can be distributed worldwide.

  15. Redirecting photosynthetic reducing power toward bioactive natural product synthesis.

    Science.gov (United States)

    Nielsen, Agnieszka Zygadlo; Ziersen, Bibi; Jensen, Kenneth; Lassen, Lærke Münter; Olsen, Carl Erik; Møller, Birger Lindberg; Jensen, Poul Erik

    2013-06-21

    In addition to the products of photosynthesis, the chloroplast provides the energy and carbon building blocks required for synthesis of a wealth of bioactive natural products of which many have potential uses as pharmaceuticals. In the course of plant evolution, energy generation and biosynthetic capacities have been compartmentalized. Chloroplast photosynthesis provides ATP and NADPH as well as carbon sources for primary metabolism. Cytochrome P450 monooxygenases (P450s) in the endoplasmic reticulum (ER) synthesize a wide spectrum of bioactive natural products, powered by single electron transfers from NADPH. P450s are present in low amounts, and the reactions proceed relatively slowly due to limiting concentrations of NADPH. Here we demonstrate that it is possible to break the evolutionary compartmentalization of energy generation and P450-catalyzed biosynthesis, by relocating an entire P450-dependent pathway to the chloroplast and driving the pathway by direct use of the reducing power generated by photosystem I in a light-dependent manner. The study demonstrates the potential of transferring pathways for structurally complex high-value natural products to the chloroplast and directly tapping into the reducing power generated by photosynthesis to drive the P450s using water as the primary electron donor.

  16. Conceptual process synthesis for recovery of natural products from plants

    DEFF Research Database (Denmark)

    Malwade, Chandrakant R.; Qu, Haiyan; Rong, Ben-Guang;

    2013-01-01

    A systematic method of conceptual process synthesis for recovery of natural products from their biological sources is presented. This methodology divides the task into two major subtasks namely, isolation of target compound from a chemically complex solid matrix of biological source (crude extract......) and purification of target compound(s) from the crude extract. Process analytical technology (PAT) is used in each step to understand the nature of material systems and separation characteristics of each separation method. In the present work, this methodology is applied to generate process flow sheet for recovery...

  17. Sites of replication of bovine respiratory syncytial virus in naturally infected calves as determined by in situ hybridization

    DEFF Research Database (Denmark)

    Viuff, B.; Uttenthal, Åse; Tegtmeier, C.

    1996-01-01

    Replication of bovine respiratory syncytial virus (BRSV) was studied in three naturally infected calves by in situ hybridization using strand-specific RNA probes. One of the calves was a 5-month-old Friesian, the other two calves were a 3-month-old and a 2-week-old Jersey. Two Jersey calves, 3 mo...

  18. Untangling the hybrid nature of modern pig genomes: a mosaic derived from biogeographically distinct and highly divergent Sus scrofa populations

    NARCIS (Netherlands)

    Bosse, M.; Megens, H.J.W.C.; Madsen, O.; Frantz, L.A.F.; Paudel, Y.; Crooijmans, R.P.M.A.; Groenen, M.

    2014-01-01

    The merging of populations after an extended period of isolation and divergence is a common phenomenon, in natural settings as well as due to human interference. Individuals with such hybrid origins contain genomes that essentially form a mosaic of different histories and demographies. Pigs are an e

  19. Studies on the chemical resistance and mechanical properties of natural polyalthia cerasoides woven fabric/glass hybridized epoxy composites

    CSIR Research Space (South Africa)

    Jayaramudu, J

    2015-01-01

    Full Text Available In the present work, natural Polyalthiacerasoide woven fabrics were extracted from the bark of the tree and using these woven fabrics/glass fibre as reinforcements and epoxy as matrix the hybrid composites were prepared by the hand lay-up technique...

  20. Natural-Synthetic Hybrid Polymers Developed via Electrospinning: The Effect of PET in Chitosan/Starch System

    OpenAIRE

    2011-01-01

    Chitosan is an amino polysaccharide found in nature, which is biodegradable, nontoxic and biocompatible. It has versatile features and can be used in a variety of applications including films, packaging, and also in medical surgery. Recently a possibility to diversify chitosan properties has emerged by combining it with synthetic materials to produce novel natural-synthetic hybrid polymers. We have studied structural and thermophysical properties of chitosan + starch + poly(ethylene terephtha...

  1. Exploiting the potential of marine natural products: structure elucidation and metagenomic approaches to biotechnological production

    OpenAIRE

    Della Sala, Gerardo

    2013-01-01

    Sponges represent the most prolific producers of novel marine bioactive secondary metabolites. In the last years, several drugs derived from marine natural products have appeared in the market, and others are in clinical trials. The aim of my research project was to exploit the unusual and often surprising chemistry of marine sponges, in the frame of the more general purpose of discovering and developing new drugs from natural products. The research work presented in this PhD Thesis was di...

  2. Transgenic hybrid poplar for sustainable and scalable production of the commodity/specialty chemical, 2-phenylethanol.

    Directory of Open Access Journals (Sweden)

    Michael A Costa

    Full Text Available Fast growing hybrid poplar offers the means for sustainable production of specialty and commodity chemicals, in addition to rapid biomass production for lignocellulosic deconstruction. Herein we describe transformation of fast-growing transgenic hybrid poplar lines to produce 2-phenylethanol, this being an important fragrance, flavor, aroma, and commodity chemical. It is also readily converted into styrene or ethyl benzene, the latter being an important commodity aviation fuel component. Introducing this biochemical pathway into hybrid poplars marks the beginnings of developing a platform for a sustainable chemical delivery system to afford this and other valuable specialty/commodity chemicals at the scale and cost needed. These modified plant lines mainly sequester 2-phenylethanol via carbohydrate and other covalently linked derivatives, thereby providing an additional advantage of effective storage until needed. The future potential of this technology is discussed. MALDI metabolite tissue imaging also established localization of these metabolites in the leaf vasculature.

  3. Life cycle assessment on microalgal biodiesel production using a hybrid cultivation system.

    Science.gov (United States)

    Adesanya, Victoria O; Cadena, Erasmo; Scott, Stuart A; Smith, Alison G

    2014-07-01

    A life cycle assessment (LCA) was performed on a putative biodiesel production plant in which the freshwater alga Chlorella vulgaris, was grown using an existing system similar to a published commercial-scale hybrid cultivation. The hybrid system couples airlift tubular photobioreactors with raceway ponds in a two-stage process for high biomass growth and lipid accumulation. The results show that microalgal biodiesel production would have a significantly lower environmental impact than fossil-derived diesel. Based on the functional unit of 1 ton of biodiesel produced, the hybrid cultivation system and hypothetical downstream process (base case) would have 42% and 38% savings in global warming potential (GWP) and fossil-energy requirements (FER) when compared to fossil-derived diesel, respectively. Sensitivity analysis was performed to identify the most influential process parameters on the LCA results. The maximum reduction in GWP and FER was observed under mixotrophic growth conditions with savings of 76% and 75% when compared to conventional diesel, respectively.

  4. Phenazines and natural products; Novel synthesis of saphenic acid

    DEFF Research Database (Denmark)

    Petersen, Lars; Jensen, Knud Jørgen; Nielsen, John

    1999-01-01

    The natural product saphenic acid (6-(1-hydroxyethyl)1-phenazinecarboxylic acid) was synthesized from readily accessible starting materials. The desired product was obtained in an overall yield of 22% for four steps with the key steps being formation of a diphenylamine, followed by cyclization un...... under alkaline and reducing conditions. Assignments of H-1 NMR spectra were achieved by homo- and heteronuclear 1D and 2D correlations. Double pulsed field gradient spin-echo one-dimensional NOESY proved especially valuable for assignment of aromatic protons....

  5. Phenazines and natural products; novel synthesis of saphenic acid

    DEFF Research Database (Denmark)

    Petersen, Lars; Jensen, Knud J.; Nielsen, John

    1999-01-01

    The natural product saphenic acid (6-(1-hydroxyethyl)1- phenazinecarboxylic acid) was synthesized from readily accessible starting materials. The desired product was obtained in an overall yield of 22% for four steps with the key steps being formation of a diphenylamine, followed by cyclization u...... under alkaline and reducing conditions. Assignments of 1H NMR spectra were achieved by homo- and heteronuclear 1D and 2D correlations. Double pulsed field gradient spin-echo one-dimensional NOESY proved especially valuable for assignment of aromatic protons....

  6. Dietary Natural Products for Prevention and Treatment of Breast Cancer.

    Science.gov (United States)

    Li, Ya; Li, Sha; Meng, Xiao; Gan, Ren-You; Zhang, Jiao-Jiao; Li, Hua-Bin

    2017-07-08

    Breast cancer is the most common cancer among females worldwide. Several epidemiological studies suggested the inverse correlation between the intake of vegetables and fruits and the incidence of breast cancer. Substantial experimental studies indicated that many dietary natural products could affect the development and progression of breast cancer, such as soy, pomegranate, mangosteen, citrus fruits, apple, grape, mango, cruciferous vegetables, ginger, garlic, black cumin, edible macro-fungi, and cereals. Their anti-breast cancer effects involve various mechanisms of action, such as downregulating ER-α expression and activity, inhibiting proliferation, migration, metastasis and angiogenesis of breast tumor cells, inducing apoptosis and cell cycle arrest, and sensitizing breast tumor cells to radiotherapy and chemotherapy. This review summarizes the potential role of dietary natural products and their major bioactive components in prevention and treatment of breast cancer, and special attention was paid to the mechanisms of action.

  7. Optimizing patient care with "natural" products: treatment of hyperpigmentation.

    Science.gov (United States)

    Woolery-Lloyd, Heather; Friedman, Adam

    2009-06-01

    Patients with skin of color suffer from different cutaneous issues when compared with skin of light complexion, and therefore management of the former must be representative of these variations. The most common pigmentary complaints in patients with skin of color are post-inflammatory hyperpigmentation, melasma and sun-induced hyperpigmentation. Often, patients with darker skin will turn to naturally occurring ingredients over synthetic analogues both to satisfy cultural preferences and to limit potential adverse effects that have been tied to synthetics. Science-based natural products can offer an attractive adjunct to conventional therapies that treat melasma, post-inflammatory hyperpigmentaion, and other dyschromias. Increasing data on the biological effects and the efficacy of natural therapies support the use of these complementary therapies in treating hyperpigmentation.

  8. Genome-wide gene expression of a natural hybrid between Saccharomyces cerevisiae and S. kudriavzevii under enological conditions.

    Science.gov (United States)

    Combina, Mariana; Pérez-Torrado, Roberto; Tronchoni, Jordi; Belloch, Carmela; Querol, Amparo

    2012-07-16

    The species Saccharomyces cerevisiae plays a predominant role in the wine making process. However, other species have been associated with must fermentation, such as Saccharomyces uvarum (Saccharomyces bayanus var. uvarum) or Saccharomyces paradoxus. Recently, yeast hybrids of different Saccharomyces species have also been reported as responsible for wine production. Yeast hybrids between the species S. cerevisiae×S. kudriavzevii isolated in wine fermentations show enhanced performance in low temperature enological conditions and increased production of interesting aroma compounds. In this work, we have studied the transcriptomic response in enological conditions of a S. cerevisiae×S. kudriavzevii hybrid strain and compared it with the reference species of S. cerevisiae and S. kudriavzevii. The results show that the hybrid strain presents an up-regulation of genes belonging to functional group translation and amino-acid metabolism. Moreover, key genes related to cold stress and production of glycerol and aroma compounds were also up-regulated. While some genes inherited regulation patterns from one of the parents, most of the up-regulated genes presented a new gene expression pattern, probably generated during the hybridization and adaptation process.

  9. The C7N aminocyclitol family of natural products.

    Science.gov (United States)

    Mahmud, Taifo

    2003-02-01

    This review covers microbial secondary metabolites classified in the family of C7N aminocyclitols, a relatively new class of natural products that is increasingly gaining recognition due to their significant biomedical and agricultural uses. Their discovery and structure determinations, their biosynthetic origin, biological properties, chemical synthesis, as well as their further development for pharmaceutical uses are described. The literature from 1970 to July 2002 is reviewed, with 269 references cited.

  10. Journal of Asian Natural Products Research简介

    Institute of Scientific and Technical Information of China (English)

    李霄茜

    2009-01-01

    @@ Journal of Asian Natural Products Research(,简称JANPR;ISSN:1028-6020;e-ISSN:1477-2213)是由英国Taylor & Francis公司出版发行的一本以亚洲传统医学中天然产品的化学和药理学研究为主要方向的国际性杂志.

  11. Five decades in the study of natural products*

    Indian Academy of Sciences (India)

    T R Govindachari

    2002-06-01

    This paper describes the five-decade long fascinating journey taken by Prof. T R Govindachari towards the study of the natural products of India. A variety of Indian plants were investigated by him for the study of their constituent alkaloids and terpenoids. The concluding part of the paper summarizes the isolation and identification of the constituents of the Neem kernel, which eventually led to the first X-ray structure determination of azadirachtin A.

  12. Cytotoxic Natural Products from Marine Sponge-Derived Microorganisms

    Directory of Open Access Journals (Sweden)

    Huawei Zhang

    2017-03-01

    Full Text Available A growing body of evidence indicates that marine sponge-derived microbes possess the potential ability to make prolific natural products with therapeutic effects. This review for the first time provides a comprehensive overview of new cytotoxic agents from these marine microbes over the last 62 years from 1955 to 2016, which are assorted into seven types: terpenes, alkaloids, peptides, aromatics, lactones, steroids, and miscellaneous compounds.

  13. Metagenomic Analysis of the Sponge Discodermia Reveals the Production of the Cyanobacterial Natural Product Kasumigamide by ‘Entotheonella’

    Science.gov (United States)

    Nakashima, Yu; Egami, Yoko; Kimura, Miki; Wakimoto, Toshiyuki; Abe, Ikuro

    2016-01-01

    Sponge metagenomes are a useful platform to mine cryptic biosynthetic gene clusters responsible for production of natural products involved in the sponge-microbe association. Since numerous sponge-derived bioactive metabolites are biosynthesized by the symbiotic bacteria, this strategy may concurrently reveal sponge-symbiont produced compounds. Accordingly, a metagenomic analysis of the Japanese marine sponge Discodermia calyx has resulted in the identification of a hybrid type I polyketide synthase-nonribosomal peptide synthetase gene (kas). Bioinformatic analysis of the gene product suggested its involvement in the biosynthesis of kasumigamide, a tetrapeptide originally isolated from freshwater free-living cyanobacterium Microcystis aeruginosa NIES-87. Subsequent investigation of the sponge metabolic profile revealed the presence of kasumigamide in the sponge extract. The kasumigamide producing bacterium was identified as an ‘Entotheonella’ sp. Moreover, an in silico analysis of kas gene homologs uncovered the presence of kas family genes in two additional bacteria from different phyla. The production of kasumigamide by distantly related multiple bacterial strains implicates horizontal gene transfer and raises the potential for a wider distribution across other bacterial groups. PMID:27732651

  14. Un nuevo híbrido natural de Dracula (Orchidaceae: Pleurothallidinae del suroccidente de Ecuador A new natural hybrid of Dracula (Orchidaceae: Pleurothallidinae from southwestern Ecuador

    Directory of Open Access Journals (Sweden)

    Bosco Javier Zambrano

    2011-09-01

    Full Text Available Se describe e ilustra un nuevo híbrido natural de Dracula de Ecuador, Dracula x pinasensis, el cual fue recientemente descubierto en el bosque húmedo de los Andes del suroccidente de Ecuador. El nuevo híbrido es comparado con Dracula mantissa, D. mopsus y D. ophioceps de Sudamérica, así como D. pusilla de Centroamérica, orquídeas con las cuales está más relacionada. Se señala a D. mopsus y D. ophioceps como los progenitores putativos de este híbrido natural.A new natural hybrid of Dracula from Ecuador is described and illustrated, Dracula x pinasensis, which was recently discovered in the Andean wet forest from Southwestern Ecuador. The new hybrid is compared with the South American D. mantissa, D. mopsus, and D. ophioceps, as well the Central American D. pusilla, the closest allies. D. mopsus and D. ophioceps are pointed out as the putative parents of this natural hybrid.

  15. An Update on Natural Products with Carbonic Anhydrase Inhibitory Activity.

    Science.gov (United States)

    Karioti, Anastasia; Carta, Fabrizio; Supuran, Claudiu T

    2016-01-01

    Carbonic anhydrases (CAs, EC 4.2.1.1) catalyze the fundamental reaction of CO2 hydration in all living organisms, being actively involved in the regulation of a plethora of patho/physiological processes. They represent a typical example of enzyme convergent evolution, as six genetically unrelated families of such enzymes were described so far. It is more than 70 years that synthetic compounds, mainly sulfonamides, have been used in clinical practice as diuretics and systemic acting antiglaucoma drugs. Recent studies using natural product libraries and isolated constituents from natural sources (such as fungi and plants) have disclosed novel chemotypes possessing carbonic anhydrase inhibition activities. These natural sources offer new opportunities in the search for new and more effective carbonic anhydrase inhibitors, and may serve as new leads for the design and development of future drugs. This review will discuss the most recent advances in the search of naturally occurring products and their synthetic derivatives that inhibit the CAs and their mechanisms of action at molecular level. Plant extracts are not considered in the present review.

  16. Rationale for a natural products approach to herbicide discovery.

    Science.gov (United States)

    Dayan, Franck E; Owens, Daniel K; Duke, Stephen O

    2012-04-01

    Weeds continue to evolve resistance to all the known modes of herbicidal action, but no herbicide with a new target site has been commercialized in nearly 20 years. The so-called 'new chemistries' are simply molecules belonging to new chemical classes that have the same mechanisms of action as older herbicides (e.g. the protoporphyrinogen-oxidase-inhibiting pyrimidinedione saflufenacil or the very-long-chain fatty acid elongase targeting sulfonylisoxazoline herbicide pyroxasulfone). Therefore, the number of tools to manage weeds, and in particular those that can control herbicide-resistant weeds, is diminishing rapidly. There is an imminent need for truly innovative classes of herbicides that explore chemical spaces and interact with target sites not previously exploited by older active ingredients. This review proposes a rationale for a natural-products-centered approach to herbicide discovery that capitalizes on the structural diversity and ingenuity afforded by these biologically active compounds. The natural process of extended-throughput screening (high number of compounds tested on many potential target sites over long periods of times) that has shaped the evolution of natural products tends to generate molecules tailored to interact with specific target sites. As this review shows, there is generally little overlap between the mode of action of natural and synthetic phytotoxins, and more emphasis should be placed on applying methods that have proved beneficial to the pharmaceutical industry to solve problems in the agrochemical industry.

  17. Natural Products as Source of Potential Dengue Antivirals

    Directory of Open Access Journals (Sweden)

    Róbson Ricardo Teixeira

    2014-06-01

    Full Text Available Dengue is a neglected disease responsible for 22,000 deaths each year in areas where it is endemic. To date, there is no clinically approved dengue vaccine or antiviral for human beings, even though there have been great efforts to accomplish these goals. Several approaches have been used in the search for dengue antivirals such as screening of compounds against dengue virus enzymes and structure-based computational discovery. During the last decades, researchers have turned their attention to nature, trying to identify compounds that can be used as dengue antivirals. Nature represents a vast reservoir of substances that can be explored with the aim of discovering new leads that can be either used directly as pharmaceuticals or can serve as lead structures that can be optimized towards the development of new antiviral agents against dengue. In this review we describe an assortment of natural products that have been reported as possessing dengue antiviral activity. The natural products are organized into classes of substances. When appropriate, structure-activity relationships are outlined. The biological assays used to assess antiviral activity are briefly described.

  18. Novel fermentation processes for manufacturing plant natural products.

    Science.gov (United States)

    Zhou, Jingwen; Du, Guocheng; Chen, Jian

    2014-02-01

    Microbial production of plant natural products (PNPs), such as terpenoids, flavonoids from renewable carbohydrate feedstocks offers sustainable and economically attractive alternatives to their petroleum-based production. Rapid development of metabolic engineering and synthetic biology of microorganisms shows many advantages to replace the current extraction of these useful high price chemicals from plants. Although few of them were actually applied on a large scale for PNPs production, continuous research on these high-price chemicals and the rapid growing global market of them, show the promising future for the production of these PNPs by microorganisms with a more economic and environmental friendly way. Introduction of novel pathways and optimization of the native cellular processes by metabolic engineering of microorganisms for PNPs production are rapidly expanding its range of cell-factory applications. Here we review recent progress in metabolic engineering of microorganisms for the production of PNPs. Besides, factors restricting the yield improvement and application of lab-scale achievements to industrial applications have also been discussed.

  19. Methylaplysinopsin and other marine natural products affecting neurotransmission.

    Science.gov (United States)

    Taylor, K M; Baird-Lambert, J A; Davis, P A; Spence, I

    1981-01-01

    Methylaplysinopsin is a novel marine natural product that, after oral administration, prevented the effects of tetrabenazine in mice and rats. Methylaplysinopsin was a short-acting inhibitor of monoamine oxidase activity with greatest potency when serotonin was the substrate studied. The brain concentration of serotonin in the mouse was increased by methylaplysinopsin over the same time course as monoamine oxidase inhibition ex vivo. Methylaplysinopsin was also a weak inhibitor of the neuronal uptake of [3H]serotonin and a potentiator of the K+-induced release of [3H]serotonin from prelabeled synaptosomes. The predicted potentiation of serotonergic neurotransmission was supported by initial neurophysiological studies in an identified serotonergic pathway in the central nervous system of Aplysia. Two other studies on the pharmacology of marine natural products are reviewed. The majority of polyhalogenated monoterpenes isolated from red algae had central nervous system depressant properties. The exception is plocamadiene A, which caused, in mice, a reversible spastic paresis lasting up to 72 hours after oral administration. The severe muscle spasm was antagonized by diazepam. The final study discussed is the effect of a variety of marine natural products on the synthesis, neuronal uptake, and metabolism of GABA. Their selectivity is discussed with regard to the effects on metabolic respiration, and the correlation of neurochemical and neurophysiological effects on these marine substances.

  20. An overview on the potential of natural products as ureas

    Directory of Open Access Journals (Sweden)

    Luzia V. Modolo

    2015-01-01

    Full Text Available Ureases, enzymes that catalyze urea hydrolysis, have received considerable attention for their impact on living organisms’ health and life quality. On the one hand, the persistence of urease activity in human and animal cells can be the cause of some diseases and pathogen infections. On the other hand, food production can be negatively affected by ureases of soil microbiota that, in turn, lead to losses of nitrogenous nutrients in fields supplemented with urea as fertilizer. In this context, nature has proven to be a rich resource of natural products bearing a variety of scaffolds that decrease the ureolytic activity of ureases from different organisms. Therefore, this work compiles the state-of-the-art researches focused on the potential of plant natural products (present in extracts or as pure compounds as urease inhibitors of clinical and/or agricultural interests. Emphasis is given to ureases of Helicobacter pylori, Canavalia ensiformis and soil microbiota although the active site of this class of hydrolases is conserved among living organisms.

  1. Automated genome mining of ribosomal peptide natural products

    Energy Technology Data Exchange (ETDEWEB)

    Mohimani, Hosein; Kersten, Roland; Liu, Wei; Wang, Mingxun; Purvine, Samuel O.; Wu, Si; Brewer, Heather M.; Pasa-Tolic, Ljiljana; Bandeira, Nuno; Moore, Bradley S.; Pevzner, Pavel A.; Dorrestein, Pieter C.

    2014-07-31

    Ribosomally synthesized and posttranslationally modified peptides (RiPPs), especially from microbial sources, are a large group of bioactive natural products that are a promising source of new (bio)chemistry and bioactivity (1). In light of exponentially increasing microbial genome databases and improved mass spectrometry (MS)-based metabolomic platforms, there is a need for computational tools that connect natural product genotypes predicted from microbial genome sequences with their corresponding chemotypes from metabolomic datasets. Here, we introduce RiPPquest, a tandem mass spectrometry database search tool for identification of microbial RiPPs and apply it for lanthipeptide discovery. RiPPquest uses genomics to limit search space to the vicinity of RiPP biosynthetic genes and proteomics to analyze extensive peptide modifications and compute p-values of peptide-spectrum matches (PSMs). We highlight RiPPquest by connection of multiple RiPPs from extracts of Streptomyces to their gene clusters and by the discovery of a new class III lanthipeptide, informatipeptin, from Streptomyces viridochromogenes DSM 40736 as the first natural product to be identified in an automated fashion by genome mining. The presented tool is available at cy-clo.ucsd.edu.

  2. Antimycobacterial natural products--an opportunity for the Colombian biodiversity.

    Science.gov (United States)

    Bueno, Juan; Coy, Ericsson David; Stashenko, Elena

    2011-12-01

    It is estimated that one-third part of the world population is infected with the tubercle bacillus. While only a small percentage of infected individuals will develop clinical tuberculosis, each year there are approximately eight million new cases and two million deaths. Mycobacterium tuberculosis is thus responsible for more human mortality than any other single microbial species. The goals of tuberculosis control are focused to cure active disease, prevent relapse, reduce transmission and avert the emergence of drug-resistance. For over 50 years, natural products have served us well on combating infectious bacteria and fungi. During the 20th century, microbial and plant secondary metabolites have helped to double our life span, reduced pain and suffering, and revolutionized medicine. Colombia is a megadiverse country with enormous potential to offer leads for new antimycobacterial drugs. The principal aim of this article is to show a state of the art on antimycobacterial natural products research in Colombia compared to the rest of the world, in order to develop programs for bioprospecting with a view to determining the biological activity for pharmaceutical and industrial application of natural products in our country.

  3. Natural products research in South Africa: 1890–2010

    Directory of Open Access Journals (Sweden)

    Siegfried E. Drewes

    2012-05-01

    Full Text Available Having spent some 50 years as an organic chemist with an interest in medicinal plant chemistry in South Africa it was relevant now to ask three questions, (1 when were natural products first utilised, (2 who were the people involved, and (3 what is the status quo? Based on older literature published in the South African Journal of Chemistry, information gleaned from attendance at innumerable chemistry conferences, and relevant literature in university archives, a great deal of information was gathered to answer the first two questions. For example, that the first veterinarian to treat cattle diseases caused by poisonous plants in the Eastern Cape was Dr Jotella Soga in the 1890s. Contributions from other prominent scientists such as Marais, Rindl, Rimington and Warren followed. From about 1940 to the 1990s, researchers concentrated mainly on the isolation of new compounds from local plants for which some indigenous knowledge was recorded. Foreign chemists also arrived and did a fair amount of ‘exploitation’ of natural products. Thus, the anti-cancer compound combretastatin was first isolated from the indigenous tree Combretum caffrum. Plant chemistry in South Africa has blossomed in the last decade, with many students from previously disadvantaged backgrounds, but with a keen interest in muti or medicinal chemistry, entering the field. Recent findings have rekindled the belief that a major development in natural products would at last emerge from Africa.

  4. Molecular and biometric characterization of natural bream × roach hybrids population in the Dobczyce Reservoir (S Poland

    Directory of Open Access Journals (Sweden)

    Maciej K Konopiński

    2015-11-01

    Full Text Available Natural hybrids of leuciscine cyprinids were investigated in a medium-sized submontane reservoir (49°52'N, 20°03'E, altitude 270 m in the Carpathian part of the Vistula basin. The material included 380 hybrid specimens (TL: 24.0–39.8 cm, SL: 19.0–31.7 cm, W: 134–714 g collected in 2006–2013. To detect their ancestry, genotypes of the 327 putative hybrids were compared to reference genotypes of 85 roaches, 115 common breams, 18 rudds, and 99 silver breams. Individuals were typed in 15 polymorphic microsatellite loci (Dubut et al. 2009, while species specific amplification of a fragment of mitochondrial cytochrome b gene was used to detect maternal origin of hybrids (Wyatt et al. 2006. Few individuals with traces of rudd and silver bream ancestry were excluded from the study. Analysis of mitochondrial DNA suggests bias towards bream maternal origin, with only 22 individuals (6,7% with roach mitochondrial DNA. The analyzed set of hybrids was composed mostly of first generation bream × roach hybrids. Only 7 individuals (2,1% showed a sign of backcrossing to bream, however, this finding has to be confirmed by analysis of further loci as it might result from presence of null alleles in roach. F2 generation hybrids were not detected. Biometric investigation of collected specimens comprised of selected morphometric (body height, and lengths of head, trunk, and tail and meristic characters (counts of scales in lateral line and soft rays in anal fin of individuals of different maternal origin. As all the analyzed differences between these categories of specimens appeared insignificant, the investigated population of hybrids may be regarded morphologically uniform.

  5. Direction of Pollination Affects Seed Productivity in (Shortleaf x Loblolly) x Loblolly Hybrids

    Science.gov (United States)

    Timothy La Farge; Davie L. Hunt

    1980-01-01

    In reciprocal crosses between shortleaf X loblolly pine hybrids and loblolly pines, seed production per pollinated flower was higher when the loblolly pine was the mother tree. We therefore recommend that loblolly pines be favored as mother trees in such work, even though storage of pollen for 1 year is required.

  6. The distribution of photosynthetic products and grain plumpness of two-line intersubspecific hybrid rice

    Institute of Scientific and Technical Information of China (English)

    ZHANGHuaiyu; WANGHuaxin; ZHANGZhongling; WUSuqiong; CHENZhiyu

    1997-01-01

    The utilization of two-line intersubspecific hybrid vigor is an important way to increase yield of rice. However, the poor plumpness of grains in many combinations is an obstacle for using the method, We analyzed the relationship between the translocation rate of photosynthetic products into grains and the grain plumpness by the aid of 14C tracer technique.

  7. Genome-Wide Gene Expressions Respond Differently to A-subgenome Origins in Brassica napus Synthetic Hybrids and Natural Allotetraploid

    Science.gov (United States)

    Zhang, Dawei; Pan, Qi; Tan, Chen; Zhu, Bin; Ge, Xianhong; Shao, Yujiao; Li, Zaiyun

    2016-01-01

    The young allotetraploid Brassica napus (2n = 38, AACC) is one of models to study genomic responses to allopolyploidization. The extraction of AA component from natural B. napus and then restitution of progenitor B. rapa should provide a unique opportunity to reveal the genome interplay for gene expressions during the evolution. Herein, B. napus hybrids (2n = 19, AC) between the extracted and extant B. rapa (2n = 20, AA) and the same B. oleracea genotype (2n = 18, CC) were studied by RNA-seq and compared with natural B. napus donor, to reveal the gene expression changes from hybridization and domestication and the effects of A genome with different origins. Upon the initial merger of two diploid genomes, additive gene expression was prevalent in these two hybrids, for non-additively expressed genes only represented a small portion of total expressed genes. A high proportion of genes exhibited expression level dominance, with no preference to either of the parental genomes. Comparison of homoeolog expressions also showed no bias toward any genomes and the parental expression patterns were often maintained in the hybrids and natural allotetraploids. Although, the overall patterns of gene expression were highly conserved between two hybrids, the extracted B. rapa responded less and appeared more compatible for hybridization than the extant B. rapa. Our results suggested that expression level dominance and homoeolog expressions bias were balanced at the initial stage of genome merger, and such balance were largely maintained during the domestication of B. napus, despite the increased extent over time. PMID:27790227

  8. Natural gas production problems : solutions, methodologies, and modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Rautman, Christopher Arthur; Herrin, James M.; Cooper, Scott Patrick; Basinski, Paul M. (El Paso Production Company, Houston, TX); Olsson, William Arthur; Arnold, Bill Walter; Broadhead, Ronald F. (New Mexico Bureau of Geology and Mineral Resources, Socorro, NM); Knight, Connie D. (Consulting Geologist, Golden, CO); Keefe, Russell G.; McKinney, Curt (Devon Energy Corporation, Oklahoma City, OK); Holm, Gus (Vermejo Park Ranch, Raton, NM); Holland, John F.; Larson, Rich (Vermejo Park Ranch, Raton, NM); Engler, Thomas W. (New Mexico Institute of Mining and Technology, Socorro, NM); Lorenz, John Clay

    2004-10-01

    Natural gas is a clean fuel that will be the most important domestic energy resource for the first half the 21st centtuy. Ensuring a stable supply is essential for our national energy security. The research we have undertaken will maximize the extractable volume of gas while minimizing the environmental impact of surface disturbances associated with drilling and production. This report describes a methodology for comprehensive evaluation and modeling of the total gas system within a basin focusing on problematic horizontal fluid flow variability. This has been accomplished through extensive use of geophysical, core (rock sample) and outcrop data to interpret and predict directional flow and production trends. Side benefits include reduced environmental impact of drilling due to reduced number of required wells for resource extraction. These results have been accomplished through a cooperative and integrated systems approach involving industry, government, academia and a multi-organizational team within Sandia National Laboratories. Industry has provided essential in-kind support to this project in the forms of extensive core data, production data, maps, seismic data, production analyses, engineering studies, plus equipment and staff for obtaining geophysical data. This approach provides innovative ideas and technologies to bring new resources to market and to reduce the overall environmental impact of drilling. More importantly, the products of this research are not be location specific but can be extended to other areas of gas production throughout the Rocky Mountain area. Thus this project is designed to solve problems associated with natural gas production at developing sites, or at old sites under redevelopment.

  9. Evaluation of new hybrid brachiaria lines in Thailand. 2. Seed production

    Directory of Open Access Journals (Sweden)

    Michael D. Hare

    2015-05-01

    Full Text Available Forty-three new hybrid bracharia lines bred at CIAT, Colombia, were evaluated for seed production in Northeast Thailand between 2006 and 2010 in 2 experiments at 2 sites, Ubon Ratchathani and Amnart Charoen. These lines were compared with Mulato II hybrid brachiaria. From the BR02 collection, 4 lines, BR02/1718, BR02/1752, BR02/1794 and BR02/0465, were granted Plant Variety Rights in 2011. BR02/1794 produced more seed than Mulato II on most occasions, including both harvests at Ubon Ratchathani and 2 of 3 harvests at Amnart Charoen. The next best yielding lines were BR02/1718 and BR02/0465, which produced more seed than Mulato II in 1 of 2 harvests at Ubon Ratchathani and 2 of 3 harvests at Amnart Charoen. Seed-set (percentage of cleaned seed to spikelets was generally very low in all hybrid lines (1–12%. The reasons for low seed-set in hybrid brachiaria grasses are discussed, including: being a common defect in newly formed apomictic forage hybrids; previous selection for seed yield not being rigorous enough; and insufficient selection at latitudes and sites where commercial brachiaria seed production is practiced.Keywords: Cayman, Cobra, Mulato II, seed yields, seed yield components.DOI: 10.17138/TGFT(394-103 

  10. Breeding drought-tolerant maize hybrids for the US corn-belt: discovery to product.

    Science.gov (United States)

    Cooper, Mark; Gho, Carla; Leafgren, Roger; Tang, Tom; Messina, Carlos

    2014-11-01

    Germplasm, genetics, phenotyping, and selection, combined with a clear definition of product targets, are the foundation of successful hybrid maize breeding. Breeding maize hybrids with superior yield for the drought-prone regions of the US corn-belt involves integration of multiple drought-specific technologies together with all of the other technology components that comprise a successful maize hybrid breeding programme. Managed-environment technologies are used to enable scaling of precision phenotyping in appropriate drought environmental conditions to breeding programme level. Genomics and other molecular technologies are used to study trait genetic architecture. Genetic prediction methodology was used to breed for improved yield performance for drought-prone environments. This was enabled by combining precision phenotyping for drought performance with genetic understanding of the traits contributing to successful hybrids in the target drought-prone environments and the availability of molecular markers distributed across the maize genome. Advances in crop growth modelling methodology are being used to evaluate the integrated effects of multiple traits for their combined effects and evaluate drought hybrid product concepts and guide their development and evaluation. Results to date, lessons learned, and future opportunities for further improving the drought tolerance of maize for the US corn-belt are discussed.

  11. 76 FR 19996 - Cooperative Agreement With the University of Mississippi's National Center for Natural Products...

    Science.gov (United States)

    2011-04-11

    ... National Center for Natural Products Research (U01) To Develop and Disseminate Botanical Natural Product... and dissemination of natural products research and science and the programs developed under the... develop and disseminate botanical natural product research with an emphasis on public safety according...

  12. Marine natural products in prevention and treatment of osteoporosis

    Directory of Open Access Journals (Sweden)

    Zahra Ghanbari

    2015-05-01

    Full Text Available Undoubtedly, pharmaceutical and nutritional factors play an important role in the prevention of age-related bone loss. According to the several studies so far, the effects of nutrients and bioactive components which are extracted from marine resources are very promising in osteoporosis. Most of these investigations have been done on various marine algae extracts. Since, algae are rich source of essential minerals, primary and secondary unique natural products, several amino acids and growth factors their extracts show favorable effects on bone metabolism. Moreover, it has been shown that marine nutrients such as marine fishes, shrimp and crabs increase the absorption of calcium and bone collagen synthesis or reduce the production of prostaglandins and decrease the deoxypyridinoline disposal. On the other hand, secondary products which are extracted and characterized from marine organisms such as mollusks, fungi, bacteria, sponges and coral reefs show anti-osteoporosis activities via the inhibition of osteoclast differentiation and the induction of apoptosis in osteoclasts like cells or stimulation of osteoblast differentiation. Although, several investigations have been done in this area, many of studies have been carried out on animal models, like ovariectomy-induced bone loss in mice. Hence, clinical investigations are warranted to develop marine natural products against bone loss and to prevent osteoporosis.

  13. Enhancement of dimethylsulfide production by anoxic stress in natural seawater

    Science.gov (United States)

    Omori, Yuko; Tanimoto, Hiroshi; Inomata, Satoshi; Wada, Shigeki; Thume, Kathleen; Pohnert, Georg

    2015-05-01

    Dimethylsulfide (DMS) is produced by phytoplankton in the ocean and plays an important role in biogeochemical cycles and climate system of the Earth. Previous field studies reported a possible relationship between DMS enhancement and anoxic condition, although the governing processes are still to be identified. Here we show the first direct evidence for the enhancement of DMS production by natural planktonic assemblages caused by anoxic stress. Under the anoxic condition, DMS production was considerably enhanced and DMS bacterial consumption was inhibited, resulting in an eightfold higher rate of gross DMS production than that under the oxic condition. Our results demonstrated that anoxic stress is one of important "environmental factors" in the marine DMS dynamics, suggesting the possible global importance due to ubiquity of anoxic conditions in the coastal oceans. This process would become more important in the future due to expansion of coastal hypoxic and anoxic zones by global warming.

  14. Mimicking a natural pathway for de novo biosynthesis: natural vanillin production from accessible carbon sources.

    Science.gov (United States)

    Ni, Jun; Tao, Fei; Du, Huaiqing; Xu, Ping

    2015-09-02

    Plant secondary metabolites have been attracting people's attention for centuries, due to their potentials; however, their production is still difficult and costly. The rich diversity of microbes and microbial genome sequence data provide unprecedented gene resources that enable to develop efficient artificial pathways in microorganisms. Here, by mimicking a natural pathway of plants using microbial genes, a new metabolic route was developed in E. coli for the synthesis of vanillin, the most widely used flavoring agent. A series of factors were systematically investigated for raising production, including efficiency and suitability of genes, gene dosage, and culture media. The metabolically engineered strain produced 97.2 mg/L vanillin from l-tyrosine, 19.3 mg/L from glucose, 13.3 mg/L from xylose and 24.7 mg/L from glycerol. These results show that the metabolic route enables production of natural vanillin from low-cost substrates, suggesting that it is a good strategy to mimick natural pathways for artificial pathway design.

  15. A novel male sterility-fertility restoration system in plants for hybrid seed production.

    Science.gov (United States)

    Singh, Surendra Pratap; Singh, Sudhir P; Pandey, Tripti; Singh, Ram Rakshpal; Sawant, Samir V

    2015-06-15

    Hybrid seeds are used for stimulated crop production, as they harness heterosis. The achievement of complete male-sterility in the female-parent and the restored-fertility in F1-hybrids are the major bottlenecks in the commercial hybrid seed production. Here, we report a male sterility-fertility restoration system by engineering the in most nutritive anther wall layer tapetum of female and male parents. In the female parent, high-level, and stringent expression of Arabidopsis autophagy-related gene BECLIN1 was achieved in the tapetum, which altered the tapetal degeneration program, leading to male sterility. This works on our previously demonstrated expression cassette based on functional complementation of TATA-box mutant (TGTA) promoter and TATA-binding protein mutant3 (TBPm3), with modification by conjugating Long Hypocotyle in Far-Red1 fragment (HFR1(NT131)) with TBPm3 (HFR1(NT131)-TBPm3) to exercise regulatory control over it. In the male parent, tapetum-specific Constitutive photo-morphogenesis1 (COP1) was expressed. The F1 obtained by crossing these engineered parents showed decreased BECLIN1 expression, which was further completely abolished when COP1-mutant (COP1(L105A)) was used as a male parent, leading to normal tapetal development and restored fertility. The system works on COP1-HFR1 interaction and COP1-mediated degradation of TBPm3 pool (HFR1(NT131)-TBPm3). The system can be deployed for hybrid seed production in agricultural crops.

  16. PRESENT STATE AND POSSIBILITIES OF MAIZE HYBRIDS SEED PRODUCTION WITH THE REVIEW ON THE EXPORT

    Directory of Open Access Journals (Sweden)

    Branimir Šimić

    2004-06-01

    Full Text Available The present seed production of maize in the Republic of Croatia is reduced in relation to the period before the Patriotic War. Production of maize seed in Croatia was between 14,000 and 21,000 tons yearly in the period from 1981 to 1986. It was reduced to 8000 tons yearly in the period from 1989 to 2001. Today, Croatia has 13 processing centres with the capacity approximately 50,000 tons of seed, but utilisation of these capacities is about 40%. Decreasing of maize seed production is caused by market reduction (less areas under the maize in Croatia and reduced export of maize hybrids seed. Before the Patriotic War, Croatia participated in the total seeds export of former Yugoslavia with 35-40%. The largest export of maize seed was 1983, with the approximately 10,700 tons. Seed export of Bc, Os and KWS hybrids was the Eastern European market, while the seed of Pioneer, SES and part of KWS hybrids was exported on the Western European market. Nowadays, production of maize hybrids at Croatia is about 5000 ha (in the world on about 1 mil. ha with the seed export of 3500 tons, approximately. Today, the largest amount of maize seed is exported in Spain, Germany, Italy, Portugal, Bosnia and Herzegovina, Macedonia, Slovenia and Turkey. The total value of maize seed production is 20 mil. Euro, approximately. Seed export should be the basic strategic aim in the program of seed production development because areas occupied with mercantile maize (approximately 400,000 ha cannot completely employ capacities for the production of seed.

  17. Production of hydrogen by thermocatalytic cracking of natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Muradov, N. [Florida Solar Energy Center, Cocoa, FL (United States)

    1996-10-01

    The conventional methods of hydrogen production from natural gas (for example, steam reforming and partial oxidation) are complex, multi-step processes that produce large quantities of CO{sub 2}. The main goal of this project is to develop a technologically simple process for hydrogen production from natural gas (NG) and other hydrocarbon fuels via single-step decomposition of hydrocarbons. This approach eliminates or significantly reduces CO{sub 2} emission. Carbon is a valuable by-product of this process, whereas conventional methods of hydrogen production from NG produce no useful by-products. This approach is based on the use of special catalysts that reduce the maximum temperature of the process from 1400-1500{degrees}C (thermal non-catalytic decomposition of methane) to 500-900{degrees}C. Transition metal based catalysts and various forms of carbon are among the candidate catalysts for the process. This approach can advantageously be used for the development of compact NG reformers for on-site production of hydrogen-methane blends at refueling stations and, also, for the production of hydrogen-rich gas for fuel cell applications. The author extended the search for active methane decomposition catalysts to various modifications of Ni-, Fe-, Mo- and Co-based catalysts. Variation in the operational parameters makes it possible to produce H{sub 2}-CH{sub 4} blends with a wide range of hydrogen concentrations that vary from 15 to 98% by volume. The author found that Ni-based catalysts are more effective at temperatures below 750{degrees}C, whereas Fe-based catalysts are effective at temperatures above 800{degrees}C for the production of hydrogen with purity of 95% v. or higher. The catalytic pyrolysis of liquid hydrocarbons (pentane, gasoline) over Fe-based catalyst was conducted. The author observed the production of a hydrogen-rich gas (hydrogen concentration up to 97% by volume) at a rate of approximately 1L/min.mL of hydrocarbon fuel.

  18. Natural products as potential cancer therapy enhancers: A preclinical update

    Directory of Open Access Journals (Sweden)

    Abed Agbarya

    2014-09-01

    Full Text Available Cancer is a multifactorial disease that arises as a consequence of alterations in many physiological processes. Recently, hallmarks of cancer were suggested that include sustaining proliferative signaling, evading growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and activating invasion and metastasis, along with two emerging hallmarks including reprogramming energy metabolism and escaping immune destruction. Treating multifactorial diseases, such as cancer with agents targeting a single target, might provide partial treatment and, in many cases, disappointing cure rates. Epidemiological studies have consistently shown that the regular consumption of fruits and vegetables is strongly associated with a reduced risk of developing chronic diseases, such as cardiovascular diseases and cancer. Since ancient times, plants, herbs, and other natural products have been used as healing agents. Moreover, the majority of the medicinal substances available today have their origin in natural compounds. Traditionally, pharmaceuticals are used to cure diseases, and nutrition and herbs are used to prevent disease and to provide an optimal balance of macro- and micro-nutrients needed for good health. We explored the combination of natural products, dietary nutrition, and cancer chemotherapeutics for improving the efficacy of cancer chemotherapeutics and negating side effects.

  19. Polyphenols-rich natural products for treatment of diabetes.

    Science.gov (United States)

    Dragan, S; Andrica, F; Serban, Maria-Corina; Timar, R

    2015-01-01

    Currently, experimental and clinical evidences showed that polyphenols-rich natural products, like nutraceuticals and food supplements, may offer unique treatment modalities in type 2 diabetes mellitus (DM), due to their biological properties. Natural products modulate the carbohydrate metabolism by various mechanisms, such as restoring beta-cells integrity and physiology, enhancing insulin releasing activity, and the glucose using. Sea buckthorn berries, red grapes, bilberries, chokeberries and popular drinks like cocoa, coffee and green tea are all rich in polyphenols and may decrease the insulin response, offer in g a natural alternative of treatment in diabetes. Therefore, researches are now focused on potential efficacies of different types of polyphenols, including flavonoids, phenolic acids, lignans, anthocyans and stilbenes. Animal and human studies showed that polyphenols modulate carbohydrate and lipid metabolism, decrease glycemia and insulin resistance, increase lipid metabolism and optimize oxidative stress and inflammatory processes. It is important to understand the proper dose and duration of supplementation with polyphenols-rich extracts in order to guide effective therapeutic interventions in diabetic patients.

  20. Natural products as potential cancer therapy enhancers: A preclinical update.

    Science.gov (United States)

    Agbarya, Abed; Ruimi, Nili; Epelbaum, Ron; Ben-Arye, Eran; Mahajna, Jamal

    2014-01-01

    Cancer is a multifactorial disease that arises as a consequence of alterations in many physiological processes. Recently, hallmarks of cancer were suggested that include sustaining proliferative signaling, evading growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and activating invasion and metastasis, along with two emerging hallmarks including reprogramming energy metabolism and escaping immune destruction. Treating multifactorial diseases, such as cancer with agents targeting a single target, might provide partial treatment and, in many cases, disappointing cure rates. Epidemiological studies have consistently shown that the regular consumption of fruits and vegetables is strongly associated with a reduced risk of developing chronic diseases, such as cardiovascular diseases and cancer. Since ancient times, plants, herbs, and other natural products have been used as healing agents. Moreover, the majority of the medicinal substances available today have their origin in natural compounds. Traditionally, pharmaceuticals are used to cure diseases, and nutrition and herbs are used to prevent disease and to provide an optimal balance of macro- and micro-nutrients needed for good health. We explored the combination of natural products, dietary nutrition, and cancer chemotherapeutics for improving the efficacy of cancer chemotherapeutics and negating side effects.

  1. Total Synthesis of the Natural Product-Pinosylvin and its Analog

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    We synthesised a natural product (10) , isolated from G.parvifolium , and its analog. The synthetic product was characterized by elemental analysis and 1H-NMR in comparision with the corresponding natural product.

  2. Evaluation of Alnus species and hybrids. [For biomass energy production

    Energy Technology Data Exchange (ETDEWEB)

    Hall, R.B. (Iowa State Univ., Ames, IA (US). Dept. of Forestry); Burgess, D. (Petawawa National Forestry Inst., Chalk River, Ontario (CA))

    1990-01-01

    Trials of a common set of seed lots representing 39 parents and five species of Alnus have been started in four countries: Belgium, Canada, the UK, and the US. Initial results indicate that cold hardiness is a problem in using A. acuminata but that sufficiently hardy A. rubra sources are available. A. glutinosa had the best growth in the nursery, and A. cordata had the best survival under severe moisture-stress conditions. A summary also is given of a workshop on alder improvement that further demonstrates the potential for developing the genus for biomass energy production. (author).

  3. ASSESSMENT OF THE PRODUCTIBILITY OF HYBRID NODES USING THE MULTI-CRITERIA METHOD

    Directory of Open Access Journals (Sweden)

    Tomasz Urbański

    2014-06-01

    Full Text Available The article presents an assessment of the productibility of hybrid nodes. The hybrid node is a new structural element the implementation of which causes numerous (especially technological problems that need to be solved. The most important element of the hybrid node is the so-called connector, the choice of which is a complex and difficult problem. It involves taking into account many aspects (constructional, strength-related, technological, economic in order to make sure that the choice is as objective as possible. Therefore, an attempt to acquire a comprehensive view at the problem requires that a set of accurate criteria be used for assessment. In this paper, the author undertakes such an attempt. The expert method presented herein allows for choosing the right connector.

  4. Entotheonella Bacteria as Source of Sponge-Derived Natural Products: Opportunities for Biotechnological Production.

    Science.gov (United States)

    Bhushan, Agneya; Peters, Eike E; Piel, Jörn

    2017-01-01

    Marine sponges belong to the oldest animals existing today. Apart from their role in recycling of carbon and nitrogen in the ocean, they are also an important source of a wide variety of structurally diverse bioactive natural products. Over the past few decades, a multitude of compounds from sponges have been discovered exhibiting diverse, pharmacologically promising activities. However, in many cases the low substance quantities present in the sponge tissue would require the collection of large amounts of sponge material, thus impeding further drug development. Recent research has focused on understanding natural product biosynthesis in sponges and on investigating symbiotic bacteria as possible production sources in order to develop sustainable production systems. This chapter covers research efforts that have taken place over the past few years involving the identification of 'Entotheonella' symbionts responsible for production of sponge compounds, as well as the elucidation of their biosynthetic routes, highlighting future biotechnological applications.

  5. Investigation on effect of fibre hybridization and orientation on mechanical behaviour of natural fibre epoxy composite

    Indian Academy of Sciences (India)

    P KALIAPPAN; R KESAVAN; B VIJAYA RAMNATH

    2017-08-01

    Nowadays bio fibre composites play a vital role by replacing conventional materials used in automotive andaerospace industries owing to their high strength to weight ratio, biodegradability and ease of production. This paper aimsto find the effect of fibre hybridization and orientation on mechanical behaviour of composite fabricated with neem, abacafibres and epoxy resin. Here, three varieties of composites are fabricated namely, composite 1 which consists of abaca fibreand glass fibre, composite 2, which consists of neem fibre and glass fibre, whereas composite 3 consists of abaca, neem fibresand glass fibres. In all the above three varieties, fibres are arranged in three types of orientations namely, horizontal (type I),vertical (type II) and 45$^{\\circ}$ inclination (type III). The result shows that composites made up of abaca and neem fibres withinclined orientation (45$^{\\circ}$) have better mechanical properties when compared with other types of composites. In addition, morphological analysis is carried out using scanning electron microscope to know the fibre distribution, fibre pull out, fibre breakage and crack propagation on tested composites.

  6. Looking for a gift of Nature: Hadron loops and hybrid mixing

    Energy Technology Data Exchange (ETDEWEB)

    Close, Frank; Thomas, Christopher

    2009-01-01

    We investigate how coupling of valence q qbar to meson pairs can modify the properties of conventional q qbar and hybrid mesons. In a symmetry limit the mixing between hybrids and conventional q qbar with the same J^PC is shown to vanish. Flavor mixing between heavy and light q qbar due to meson loops is shown to be dual to the

  7. Hybridization of natural systems with advanced treatment processes for organic micropollutant removals: new concepts in multi-barrier treatment.

    Science.gov (United States)

    Sudhakaran, Sairam; Maeng, Sung Kyu; Amy, Gary

    2013-07-01

    Organic micropollutants (OMPs) represent a major constraint in drinking water supply. In the past, emphasis has been on individual treatment processes comprising conventional treatment (coagulation, sedimentation, and filtration) followed by advanced treatment processes (adsorption, ion-exchange, oxidation, and membrane separation). With the depletion of water resources and high demand for power and chemical usage, efforts need to be made to judiciously use advanced treatment processes. There is a new interest in multiple barriers with synergies in which two coupled processes can function as a hybrid process. Within the context of this paper, the hybrid processes include a natural treatment process coupled with an advanced process. Pilot/full-scale studies have shown efficient removal of OMPs by these hybrid processes. With this hybridization, the usage of resources such as power and chemicals can be reduced. In this study, coupling/hybridization of aquifer recharge and recovery (ARR) with oxidation (O3), advanced oxidation process which involves OH radicals (AOP), nanofiltration (NF), reverse osmosis (RO) and granular activated carbon (GAC) adsorption for OMP removal was studied. O3 or AOP as a pre-treatment and GAC, NF, RO, or UV/chlorination as a post-treatment to ARR was studied. NF can be replaced by RO for removal of OMPs since studies have shown similar performance of NF to RO for removal of many OMPs, thereby reducing costs and providing a more sustainable approach.

  8. Hybridization Between Natural Extract of Angelica gigas Nakai and Inorganic Nanomaterial of Layered Double Hydroxide via Reconstruction Reaction.

    Science.gov (United States)

    Kim, Tae-Hyun; Kim, Hyoung-Jun; Choi, Ae-Jin; Choi, Hyun-Jin; Oh, Jae-Min

    2016-01-01

    We have hybridized layered double hydroxide (LDH) with Angelica gigas Nakai root extract (AGNR) through reversible dehydration-rehydration reaction which is known as reconstruction. LDHs having well-ordered hydrotalcite-like crystal structure and average size 250 ± 20 nm were prepared by hydrothermal method. The root of Angelica gigas Nakai, which has been utilized in the treatment of female disorders as herbal medicine, was treated with methanol to obtain extract. Pristine LDHs were calcined at 400 °C for 8 hours to obtain layered double oxide (LDO), which was further dispersed into extract solution with various AGNR/LDO weight ratios, 0.11, 0.21 and 0.43. The extract content in each hybrid increased in proportion to initial AGNR/LDO ratio, showing the highest content of ~12%. The zeta potential of LDH shifted from +44 mV to +20 mV upon hybridization with extract, which was attributed to the adsorption of negatively charged organic moieties in AGNR on LDH surface. The scanning electron microscopic (SEM) results exhibited that the random stacking of LDH nanolayers resulted in LDH-AGNR hybrid with house-of-cards structure, of which inter-particle cavity serves nano-reservoir for natural extract. According to quantitative analyses, it was revealed that the content of active components in AGNR increased when they were hybridized with LDHs compared with those in AGNR alone.

  9. Hybridization of natural systems with advanced treatment processes for organic micropollutant removals: New concepts in multi-barrier treatment

    KAUST Repository

    Sudhakaran, Sairam

    2013-07-01

    In the past, emphasis has been on individual treatment processes comprising conventional treatment (coagulation, sedimentation, and filtration) followed by advanced treatment processes (adsorption, ion-exchange, oxidation, and membrane separation). With the depletion of water resources and high demand for power and chemical usage, efforts need to be made to judiciously use advanced treatment processes. There is a new interest in multiple barriers with synergies in which two coupled processes can function as a hybrid process. Within the context of this paper, the hybrid processes include a natural treatment process coupled with an advanced process. Pilot/full-scale studies have shown efficient removal of OMPs by these hybrid processes. With this hybridization, the usage of resources such as power and chemicals can be reduced. In this study, coupling/hybridization of aquifer recharge and recovery (ARR) with oxidation (O3), advanced oxidation process which involves OH radicals (AOP), nanofiltration (NF), reverse osmosis (RO) and granular activated carbon (GAC) adsorption for OMP removal was studied. O3 or AOP as a pre-treatment and GAC, NF, RO, or UV/chlorination as a post-treatment to ARR was studied. NF can be replaced by RO for removal of OMPs since studies have shown similar performance of NF to RO for removal of many OMPs, thereby reducing costs and providing a more sustainable approach. © 2013 Elsevier Ltd.

  10. Hybrid energy system evaluation in water supply system energy production: neural network approach

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Fabio V.; Ramos, Helena M. [Civil Engineering Department, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001, Lisbon (Portugal); Reis, Luisa Fernanda R. [Universidade de Sao Paulo, EESC/USP, Departamento de Hidraulica e Saneamento., Avenida do Trabalhador Saocarlense, 400, Sao Carlos-SP (Brazil)

    2010-07-01

    Water supply systems are large consumers of energy and the use of hybrid systems for green energy production is this new proposal. This work presents a computational model based on neural networks to determine the best configuration of a hybrid system to generate energy in water supply systems. In this study the energy sources to make this hybrid system can be the national power grid, micro-hydro and wind turbines. The artificial neural network is composed of six layers, trained to use data generated by a model of hybrid configuration and an economic simulator - CES. The reason for the development of an advanced model of forecasting based on neural networks is to allow rapid simulation and proper interaction with hydraulic and power model simulator - HPS. The results show that this computational model is useful as advanced decision support system in the design of configurations of hybrid power systems applied to water supply systems, improving the solutions in the development of its global energy efficiency.

  11. Hybrid energy system evaluation in water supply system energy production: neural network approach

    Directory of Open Access Journals (Sweden)

    Fabio V. Goncalves, Helena M. Ramos, Luisa Fernanda R. Reis

    2010-01-01

    Full Text Available Water supply systems are large consumers of energy and the use of hybrid systems for green energy production is this new proposal. This work presents a computational model based on neural networks to determine the best configuration of a hybrid system to generate energy in water supply systems. In this study the energy sources to make this hybrid system can be the national power grid, micro-hydro and wind turbines. The artificial neural network is composed of six layers, trained to use data generated by a model of hybrid configuration and an economic simulator – CES. The reason for the development of an advanced model of forecasting based on neural networks is to allow rapid simulation and proper interaction with hydraulic and power model simulator – HPS. The results show that this computational model is useful as advanced decision support system in the design of configurations of hybrid power systems applied to water supply systems, improving the solutions in the development of its global energy efficiency.

  12. Water for wood products versus nature, food or feed

    Science.gov (United States)

    Schyns, Joep; Booij, Martijn; Hoekstra, Arjen

    2017-04-01

    more water available for the generation of other ecosystem services. Our findings contribute to a more complete picture of the human appropriation of water and the understanding of the interlinkages between the SDGs, thus feeding the debate on water for wood products versus nature, food or feed.

  13. Environmental review of natural gas production in Lake Erie

    Energy Technology Data Exchange (ETDEWEB)

    O' Shea, K. [Dillon Consulting Ltd., Cambridge, ON (Canada)

    2002-07-01

    The water of Lake Erie is used as a source of drinking water for Ontario, New York, Pennsylvania, Ohio and Michigan. An environmental review has been conducted to determine the impact of drilling operations on the overall ecology of the lake. Since 1913, 2000 natural gas wells have been drilled in Lake Erie, of which 550 currently produce gas and account for 75 per cent of Ontario's total gas production. 180 wells are shut-in or suspended and the remaining wells have been abandoned. The gas wells are connected to onshore production facilities by approximately 1,600 km of small diameter pipelines that lie buried near shore or on top of the lake bed. Nearly 90 per cent of the in-lake infrastructure is in water depths of more than 20 metres. Talisman Energy is actively involved with the Canadian Coast Guard, the Department of Fisheries and Oceans, and the Ministry of Natural Resources to ensure cooperation between regulators and off-shore personnel. The environmental assessment of natural gas production in Lake Erie included a review of regulatory and best management practices, a biophysical overview of the lake, and a review of drilling practices, well completions, handling of waste streams, materials management, operations inspections, wastewater discharge, air emissions, and oil spills. It was revealed that for most drilling programs, cuttings are washed and discharged to the Lake. Ongoing testing will determine the impact that this practice has on benthic populations. The drill muds used for drilling operations are water based, environmentally friendly, and re-used between well locations. For completion programs, all well activities are closed circuit operations. Wells are abandoned through plugging with cement, removing wellheads and casing below the lake bottom. There has been a reported volume of about 23,000 litres of spilled product from 1990 to 2001, of which 68 per cent has come from 3 industrial companies that operate near Lake Erie. The offshore gas

  14. Bioactive Natural Products of Marine Sponges from the Genus Hyrtios

    Directory of Open Access Journals (Sweden)

    Nourhan Hisham Shady

    2017-05-01

    Full Text Available Marine sponges are known as a rich source for novel bioactive compounds with valuable pharmacological potential. One of the most predominant sponge genera is Hyrtios, reported to have various species such as Hyrtios erectus, Hyrtios reticulatus, Hyrtios gumminae, Hyrtios communis, and Hyrtios tubulatus and a number of undescribed species. Members of the genus Hyrtios are a rich source of natural products with diverse and valuable biological activities, represented by different chemical classes including alkaloids, sesterterpenes and sesquiterpenes. This review covers the literature until June 2016, providing a complete survey of all compounds isolated from the genus Hyrtios with their corresponding biological activities whenever applicable.

  15. A general enantioselective route to the chamigrene natural product family

    KAUST Repository

    White, David E.

    2010-06-01

    Described in this report is an enantioselective route toward the chamigrene natural product family. The key disconnections in our synthetic approach include sequential enantioselective decarboxylative allylation and ring-closing olefin metathesis to form the all-carbon quaternary stereocenter and spirocyclic core present in all members of this class of compounds. The generality of this strategy is demonstrated by the first total syntheses of elatol and the proposed structure of laurencenone B, as well as the first enantioselective total syntheses of laurencenone C and α-chamigrene. A brief exploration of the substrate scope of the enantioselective decarboxylative allylation/ring-closing metathesis sequence with fully substituted vinyl chlorides is also presented.

  16. NMR structural studies of oligosaccharides and other natural products

    DEFF Research Database (Denmark)

    Kjærulff, Louise

    produce secondary metabolites for signaling and competing against other organisms, and these molecules are important in drug discovery due to their inherent biological activities. From a marine Photobacterium (P. halotolerans) we isolated the solonamides and the ngercheumicins, two families of cyclic....... fijiensis, was also investigated for production of novel secondary metabolites, and a new pyranonigrin (E) was isolated and structure elucidated by NMR spectroscopy along with JBIR-74 and decumbenone A, two known metabolites previously isolated from Aspergillus and Penicillium species. Oligosaccharides...... with respect to n+1JHH between these two experiments, observed in the nJCH HMBC cross peak. Through a double editing procedure this enables straightforward determination of both sign and magnitude of n+1JHH, including for very small coupling constants. Excellent results were obtained for the natural product...

  17. Natural products from Bacillus subtilis with antimicrobial properties☆

    Institute of Scientific and Technical Information of China (English)

    Tao Wang; Yafei Liang; Mianbin Wu; Zhengjie Chen; Jianping Lin; Lirong Yang

    2015-01-01

    Bacil us subtilis produces many chemical y-diverse secondary metabolites of interest to chemists and biologists. Based on this, this review gives a detalled overview of the natural components produced by B. subtilis including cyclic lipopeptides, polypeptides, proteins (enzymes), and non-peptide products. Their structures, bioactive ac-tivities and the relevant variants as novel lead structures for drug discovery are also described. The challenging effects of fermentation metabolites, isolation and purification, as wel as the overproduction of bioactive com-pounds from B. subtilis by metabolic engineering, were also highlighted. Systematical y exploring biosynthetic routes and the functions of secondary metabolites from B. subtilis may not only be beneficial in improving yields of the products, but also in helping them to be used in food industry and public medical service on a large-scale.

  18. Natural Dietary and Herbal Products in Anti-Obesity Treatment.

    Science.gov (United States)

    Sun, Nan-Nong; Wu, Tsung-Yen; Chau, Chi-Fai

    2016-10-11

    The prevalence of overweight and obesity is on the rise around the world. Common comorbidities associated with obesity, particularly diabetes, hypertension, and heart disease have an impact on social and financial systems. Appropriate lifestyle and behavior interventions are still the crucial cornerstone to weight loss success, but maintaining such a healthy lifestyle is extremely challenging. Abundant natural materials have been explored for their obesity treatment potential and widely used to promote the development of anti-obesity products. The weight loss segment is one of the major contributors to the overall revenue of the dietary supplements market. In this review, the anti-obesity effects of different dietary or herbal products, and their active ingredients and mechanisms of action against obesity will be discussed.

  19. The snowmaker: nature identical snow production in the laboratory

    Science.gov (United States)

    Schleef, S.; Jaggi, M.; Loewe, H.; Schneebeli, M.

    2013-12-01

    Using natural snow for laboratory experiments can be tricky due to shortage of winter periods and snowfall, difficulties of sample casting and transport, and the great variability of natural snow due to the varying conditions of crystal growth in the clouds. This hinders repeatable laboratory experiments with reproducible specimen and microstructural characteristics. To minimize experimental uncertainties we designed an improved machine called snowmaker, which enables us to produce nature-identical snow in a cold laboratory under well defined conditions. The snowmaker is based on well-known principles: warm humid air from a heated water basin is advected into a cold nucleation chamber where the vapor resublimates on stretched Nylon wires. Crystals are automatically harvested by a motor driven brush rack and collected in a box, thereby several kilograms of snow can be produced per day with minimum maintenance. The excess vapor is collected in a moisture trap to avoid frost in the laboratory. The entire construction is designed as a rolling, modular assembly system which can easily carried out of the laboratory for defrosting. In addition to previous attempts we focus on the reproducibility of the samples and the comparison to natural snow down to the microscale. We show that the settings of water temperature and cold laboratory temperature facilitates the production of different crystal shapes like dendrites and needles in a reproducible way. Besides photography, we analyzed the microstructure of snowmaker crystals in aggregated specimen by X-ray microtomography. Depending on the settings we can create reproducible samples with density of 50-170 kg/m3 and specific surface areas of 50-80 mm-1. We briefly touch similarities between artificial and natural snow samples with respect to crystal habit, microstructural parameters and short-time metamorphism.

  20. Heterosis in locally adapted sorghum genotypes and potential of hybrids for increased productivity in contrasting environments in Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Taye T. Mindaye; Emma S. Mace; Ian D. Godwin; David R. Jordan

    2016-01-01

    Increased productivity in sorghum has been achieved in the developed world using hybrids. Despite their yield advantage, introduced hybrids have not been adopted in Ethiopia due to the lack of adaptive traits, their short plant stature and small grain size. This study was conducted to investigate hybrid performance and the magnitude of heterosis of locally adapted genotypes in addition to introduced hybrids in three contrasting environments in Ethiopia. In total, 139 hybrids, derived from introduced seed parents crossed with locally adapted genotypes and introduced R lines, were evaluated. Overall, the hybrids matured earlier than the adapted parents, but had higher grain yield, plant height, grain number and grain weight in all environments. The lowland adapted hybrids displayed a mean better parent heterosis (BPH) of 19%, equating to 1160 kg ha−1 and a 29%mean increase in grain yield, in addition to increased plant height and grain weight, in comparison to the hybrids derived from the introduced R lines. The mean BPH for grain yield for the highland adapted hybrids was 16%in the highland and 52%in the intermediate environment equating to 698 kg ha−1 and 2031 kg ha−1, respectively, in addition to increased grain weight. The magnitude of heterosis observed for each hybrid group was related to the genetic distance between the parental lines. The majority of hybrids also showed superiority over the standard check varieties. In general, hybrids from locally adapted genotypes were superior in grain yield, plant height and grain weight compared to the high parents and introduced hybrids indicating the potential for hybrids to increase productivity while addressing farmers' required traits.

  1. Effect of natural extracts pH on morphological characteristics of hybrid materials based on gold nanoparticles

    Science.gov (United States)

    Olenic, L.; Vulcu, A.; Chiorean, I.; Crisan, M.; Berghian-Grosan, C.; Dreve, S.; David, L.; Tudoran, L. B.; Kacso, I.; Bratu, I.; Neamtu, C.; Voica, C.

    2013-11-01

    In the present paper we have investigated the pH influence on the morphology of some new hybrid materials based on gold nanoparticles and natural extracts from fruits of Romanian native plants of Adoxaceae family (Viburnum opulus L. and Sambucus nigra L.). It is well known that the natural plants extracts are beneficial for humans thanks to their antioxidant, anti-inflammatory and immunomodulatory effects. The biological activity of these berries is mainly due to their high content of anthocyanins and other polyphenols. The nanoparticles facilitate the penetration of substances in skin, enhancing their antimitotic, anti-inflammatory and antibiotic properties. We have chosen the optimal method to get these materials in which gold nanoparticles of 10-80 nm were obtained. We characterized them by UV-Vis and FT-IR spectroscopy, by TEM and DSC. Creams prepared with the hybrid materials have been tested on psoriatic lesions and the medical results emphasized a remarkable improvement in this diseases.

  2. US production of natural gas from tight reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-18

    For the purposes of this report, tight gas reservoirs are defined as those that meet the Federal Energy Regulatory Commission`s (FERC) definition of tight. They are generally characterized by an average reservoir rock permeability to gas of 0.1 millidarcy or less and, absent artificial stimulation of production, by production rates that do not exceed 5 barrels of oil per day and certain specified daily volumes of gas which increase with the depth of the reservoir. All of the statistics presented in this report pertain to wells that have been classified, from 1978 through 1991, as tight according to the FERC; i.e., they are ``legally tight`` reservoirs. Additional production from ``geologically tight`` reservoirs that have not been classified tight according to the FERC rules has been excluded. This category includes all producing wells drilled into legally designated tight gas reservoirs prior to 1978 and all producing wells drilled into physically tight gas reservoirs that have not been designated legally tight. Therefore, all gas production referenced herein is eligible for the Section 29 tax credit. Although the qualification period for the credit expired at the end of 1992, wells that were spudded (began to be drilled) between 1978 and May 1988, and from November 5, 1990, through year end 1992, are eligible for the tax credit for a subsequent period of 10 years. This report updates the EIA`s tight gas production information through 1991 and considers further the history and effect on tight gas production of the Federal Government`s regulatory and tax policy actions. It also provides some high points of the geologic background needed to understand the nature and location of low-permeability reservoirs.

  3. Simulation of the performance and economical study of a hybrid thermal desalination (solar and natural gas); Simulacao do desempenho e estudo economico de um dessalinizador hibrido (solar e gas natural)

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Maria E.V. da; Coutinho, Lecimara D.E.; Soares, Bruno de L. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil); Schwarzer, Klemens [Universidade de Ciencias Aplicadas de Aachen (Germany); Campos, Michel F. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    This article presents a simulation of the performance and the results of an economic study of a hybrid thermal desalination equipment to produce drinkable water using solar energy and natural gas at its energy sources. The components of the desalination equipment are two solar flat plate collectors with reflectors, a natural gas burner, and a desalination tower. A piping circuit connects the tower to the collectors and the burner. In this circuit, a fluid transports heat from the thermal sources (collectors or burner) to the salty water in the first stage of the tower. When the salty water receives heat, it warms up and evaporates. The vapor produced flows up the bottom walls of the next stage, where it condenses, as it transfers the phase change heat to the water in this upper stage. The condensate flows in lateral channels to be collected outside the tower. Experimental measurements results obtained for a desalination unit with 4m{sup 2} of collector area and a seven stage tower, and the natural gas properties were used in the calculation. In the economic study, fabrication, installation, and maintenance costs were included. The results also show the water daily production for solar and hybrid. (author)

  4. The new hybrid ceramic beads synthesized from natural minerals and titanium dioxide for the waste water cleaning

    OpenAIRE

    SATA, Akiyoshi; Hirose, Masanao; Kurawaki, Junichi; "KUSUMOTO, Yoshifumi"; HAYAKAWA, Katumitu

    2006-01-01

    Porous hybrid ceramic beads were synthesized by burning at 1090°C under a reductive atmosphere. They consist of the natural mineral (graphite silica, GS), the pyroclastic deposit “shirasu” and titanium dioxide. They showed the bleaching of the aqueous dyestuff solutions (rhodamin B, acridine orange, methyl orange, methylene blue) and the degradation of a surfactant dodecyltrimethylpyridinium bromide and humic acid. The decolorizing rate of dye stuff was monitored by the absorpt...

  5. Potential anti-inflammatory natural products from marine algae.

    Science.gov (United States)

    Fernando, I P Shanura; Nah, Jae-Woon; Jeon, You-Jin

    2016-12-01

    Inflammatory diseases have become one of the leading causes of health issue throughout the world, having a considerable influence on healthcare costs. With the emerging developments in natural product, synthetic and combinatorial chemistry, a notable success has been achieved in discovering natural products and their synthetic structural analogs with anti-inflammatory activity. However, many of these therapeutics have indicated detrimental side effects upon prolonged usage. Marine algae have been identified as an underexplored reservoir of unique anti-inflammatory compounds. These include polyphenols, sulfated polysaccharides, terpenes, fatty acids, proteins and several other bioactives. Consumption of these marine algae could provide defense against the pathophysiology of many chronic inflammatory diseases. With further investigation, algal anti-inflammatory phytochemicals have the potential to be used as therapeutics or in the synthesis of structural analogs with profound anti-inflammatory activity with reduced side effects. The current review summarizes the latest knowledge about the potential anti-inflammatory compounds discovered from marine algae. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. The Impending Renaissance in Discovery & Development of Natural Products.

    Science.gov (United States)

    Pawar, Sandip V; Ho, Joe C H; Yadav, Ganapati D; Yadav, Vikramaditya G

    2017-01-01

    Antibiotics are wonder drugs. Unfortunately, owing to overuse, antibiotic resistance is now a serious problem. Society now finds itself in the post-antibiotic era, and the threat of infectious diseases is on the rise. New antibiotics are sorely needed. There is strong evidence that suggests natural products are an attractive source of new antimicrobials. They posses desirable structural and chemical properties that make them potent thearpeutics. However, steep tehnological challenges associated with screening and manufacturing these molecules has stifled the discovery, development and marketing of new antimicrobials. To this end, two recent scientific developments are poised to redress this situation. The recent development of metagenomics and ancillary high-throughput screening technologies has exponentiated the volume of useful genetic sequence information that can be screened for antimicrobial discovery. These approaches have been instrumental in the discovery of new antibiotics from soil and marine environments. Secondly, a new manufacturing paradigm employing metabolic engineering as its engine has greatly accelerated the path to market for these molecules, in addition to improving the atom and energy economy of antimicrobial manufacturing. We outine these developments in this review, and provide a perspective on integrating next-generation approaches such as metagenomics and metabolic engineering with traditional methodologies for discovering and manufacturing antimicrobial natural products in order to unleash a rennaissance in the discovery and development of antimicrobials.

  7. The potential of natural products for targeting PPARα

    Directory of Open Access Journals (Sweden)

    Daniela Rigano

    2017-07-01

    Full Text Available Peroxisome proliferator activated receptors (PPARs α, -γ and -β/δ are ligand-activated transcription factors and members of the superfamily of nuclear hormone receptor. These receptors play key roles in maintaining glucose and lipid homeostasis by modulating gene expression. PPARs constitute a recognized druggable target and indeed several classes of drugs used in the treatment of metabolic disease symptoms, such as dyslipidemia (fibrates, e.g. fenofibrate and gemfibrozil and diabetes (thiazolidinediones, e.g. rosiglitazone and pioglitazone are ligands for the various PPAR isoforms. More precisely, antidiabetic thiazolidinediones act on PPARγ, while PPARα is the main molecular target of antidyslipidemic fibrates. Over the past few years, our understanding of the mechanism underlying the PPAR modulation of gene expression has greatly increased. This review presents a survey on terrestrial and marine natural products modulating the PPARα system with the objective of highlighting how the incredible chemodiversity of natural products can provide innovative leads for this “hot” target.

  8. Paraptosis in the anti-cancer arsenal of natural products.

    Science.gov (United States)

    Lee, Dongjoo; Kim, In Young; Saha, Sharmistha; Choi, Kyeong Sook

    2016-06-01

    Given the problems with malignant cancer cells showing innate and acquired resistance to apoptosis, we need alternative means to induce cell death in cancer. Paraptosis is a type of programmed cell death that is characterized by dilation of the endoplasmic reticulum (ER) and/or mitochondria. Although relatively little is known regarding the molecular basis of paraptosis, the underlying mechanism clearly differs from that of apoptosis. Recent studies have shown that various natural products, including curcumin, celastrol, 15d-PGJ2, ophiobolin A, and paclitaxel, demonstrate anti-cancer effects by inducing the paraptosis-associated cell death, which was commonly characterized by vacuolation derived from the ER. Perturbation of cellular proteostasis due to proteasomal inhibition and disruption of sulfhydryl homeostasis, generation of reactive oxygen species, and/or imbalanced homeostasis of ions (e.g., Ca(2+) and K(+)) appear to contribute to the accumulation of misfolded protein and proteotoxicity in this process. Given the pathophysiological importance of paraptosis and the debate regarding the importance of apoptosis in solid tumor, we need to collect the available knowledge regarding paraptosis and suggest future directions in the field. Here, we review the morphological and biochemical features of paraptosis, the natural products that induce paraptosis-associated cell death, their proposed mechanisms, and the significance of paraptosis as a potential anti-cancer strategy. Such work and future clarifications should enable the development of new strategies for preventing cancer and/or combating malignant cancer.

  9. Total Synthesis of Natural Products Using Hypervalent Iodine Reagents

    Science.gov (United States)

    Maertens, Gaetan; L'homme, Chloe; Canesi, Sylvain

    2014-12-01

    We present a review of natural product syntheses accomplished in our laboratory during the last five years. Each synthetic route features a phenol dearomatization promoted by an environmentally benign hypervalent iodine reagent. The dearomatizations demonstrate the “aromatic ring umpolung” concept, and involve stereoselective remodeling of the inert unsaturations of a phenol into a highly functionalized key intermediate that may contain a quaternary carbon center and a prochiral dienone system. Several new oxidative strategies were employed, including transpositions (1,3-alkyl shift and Prins-pinacol), a polycyclization, an ipso rearrangement, and direct nucleophilic additions at the phenol para position. Several alkaloids, heterocyclic compounds, and a polycyclic core have been achieved, including sceletenone (a serotonin reuptake inhibitor), acetylaspidoalbidine (an antitumor agent), fortucine (antiviral and antitumor), erysotramidine (curare-like effect), platensimycin (an antibiotic), and the main core of a kaurane diterpene (immunosuppressive agent and stimulator of apoptosis). These concise and in some cases enantioselective syntheses effectively demonstrate the importance of hypervalent iodine reagents in the total synthesis of bioactive natural products.

  10. Total Synthesis of Natural Products Using Hypervalent Iodine Reagents

    Directory of Open Access Journals (Sweden)

    Gaetan eMaertens

    2015-01-01

    Full Text Available We present a review of natural product syntheses accomplished in our laboratory during the last five years. Each synthetic route features a phenol dearomatization promoted by an environmentally benign hypervalent iodine reagent. The dearomatizations demonstrate the aromatic ring umpolung concept, and involve stereoselective remodeling of the inert unsaturations of a phenol into a highly functionalized key intermediate that may contain a quaternary carbon center and a prochiral dienone system. Several new oxidative strategies were employed, including transpositions (1,3-alkyl shift and Prins-pinacol, a polycyclization, an ipso rearrangement, and direct nucleophilic additions at the phenol para position. Several alkaloids, heterocyclic compounds, and a polycyclic core have been achieved, including sceletenone (a serotonin reuptake inhibitor, acetylaspidoalbidine (an antitumor agent, fortucine (antiviral and antitumor, erysotramidine (curare-like effect, platensimycin (an antibiotic, and the main core of a kaurane diterpene (immunosuppressive agent and stimulator of apoptosis. These concise and in some cases enantioselective syntheses effectively demonstrate the importance of hypervalent iodine reagents in the total synthesis of bioactive natural products.

  11. Systems biology approaches to understand natural products biosynthesis

    Directory of Open Access Journals (Sweden)

    Cuauhtemoc eLicona-Cassani

    2015-12-01

    Full Text Available Actinomycetes populate soils and aquatic sediments which impose biotic and abiotic challenges for their survival. As a result, actinomycetes metabolism and genomes have evolved to produce an overwhelming diversity of specialized molecules. Polyketides, non-ribosomal peptides, post-translationally modified peptides, lactams and terpenes are well known bioactive natural products with enormous industrial potential. Accessing such biological diversity has proven difficult due to the complex regulation of cellular metabolism in actinomycetes and to the sparse knowledge of their physiology. The past decade, however, has seen the development of omics technologies that have significantly contributed to our better understanding of their biology. Key observations have contributed towards a shift in the exploitation of actinomycetes biology, such as using their full genomic potential, activating entire pathways through key metabolic elicitors and pathway engineering to improve biosynthesis. Here, we review recent efforts devoted to achieving enhanced discovery, activation and manipulation of natural product biosynthetic pathways in model actinomycetes using genome-scale biological datasets.

  12. Hybrid Nitrous Oxide Production from a Partial Nitrifying Bioreactor: Hydroxylamine Interactions with Nitrite.

    Science.gov (United States)

    Terada, Akihiko; Sugawara, Sho; Hojo, Keisuke; Takeuchi, Yuki; Riya, Shohei; Harper, Willie F; Yamamoto, Tomoko; Kuroiwa, Megumi; Isobe, Kazuo; Katsuyama, Chie; Suwa, Yuichi; Koba, Keisuke; Hosomi, Masaaki

    2017-03-07

    The goal of this study was to elucidate the mechanisms of nitrous oxide (N2O) production from a bioreactor for partial nitrification (PN). Ammonia-oxidizing bacteria (AOB) enriched from a sequencing batch reactor (SBR) were subjected to N2O production pathway tests. The N2O pathway test was initiated by supplying an inorganic medium to ensure an initial NH4(+)-N concentration of 160 mg-N/L, followed by (15)NO2(-) (20 mg-N/L) and dual (15)NH2OH (each 17 mg-N/L) spikings to quantify isotopologs of gaseous N2O ((44)N2O, (45)N2O, and (46)N2O). N2O production was boosted by (15)NH2OH spiking, causing exponential increases in mRNA transcription levels of AOB functional genes encoding hydroxylamine oxidoreductase (haoA), nitrite reductase (nirK), and nitric oxide reductase (norB) genes. Predominant production of (45)N2O among N2O isotopologs (46% of total produced N2O) indicated that coupling of (15)NH2OH with (14)NO2(-) produced N2O via N-nitrosation hybrid reaction as a predominant pathway. Abiotic hybrid N2O production was also observed in the absence of the AOB-enriched biomass, indicating multiple pathways for N2O production in a PN bioreactor. The additional N2O pathway test, where (15)NH4(+) was spiked into 400 mg-N/L of NO2(-) concentration, confirmed that the hybrid N2O production was a dominant pathway, accounting for approximately 51% of the total N2O production.

  13. Prevention of microbial communities: novel approaches based natural products.

    Science.gov (United States)

    Mogosanu, George D; Grumezescu, Alexandru M; Huang, Keng-Shiang; Bejenaru, Ludovic E; Bejenaru, Cornelia

    2015-01-01

    Firmly attached to different living or non-living, solid or fluid surfaces rich in nutrients and moisture, microbial biofilm is a matter of great interest due to its major importance for the healthcare community. Depending on common strategies such as mutual protection and hibernation (quiescent bacteria), the resistance, survival and virulence of microbial communities have large implications for human pathology, clinical environment and biomedical devices. The microbial biofilm is continuously changing, stimulating inflammation, increasing vascular permeability and preventing the action of macrophages. About 80% of human infections affecting the gastrointestinal, genitourinary and respiratory systems, oral mucosa and teeth, eyes, middle ear and skin are caused by biofilm-associated microorganisms. Therefore, the search for modern strategies is even more important as microbial biofilms resistant to conventional antibiotics, antiseptics and disinfectants are involved in the frequent treatment failures of some chronic inflammatory diseases and wounds. Natural products containing secondary metabolites, such as aromatic compounds, sulphurated derivatives, terpenoids (essential oils) and alkaloids as quorum-sensing inhibitors and biofilm disruptors, are promising alternatives for the prophylaxis and treatment of chronic infections. Surface modification of medical devices with non-polar functionalized nanoparticles stabilizes the natural compounds antibiofilm activity and inhibits microbial adhesion and biofilm formation and growth for a longer period of time. In this regard, an interdisciplinary approach is needed due to the large number of natural derivatives alone or in combination with biocompatible and biodegradable micro-/ nano-engineered materials.

  14. Probiotics stimulate production of natural antibodies in chickens.

    Science.gov (United States)

    Haghighi, Hamid R; Gong, Jianhua; Gyles, Carlton L; Hayes, M Anthony; Zhou, Huaijun; Sanei, Babak; Chambers, James R; Sharif, Shayan

    2006-09-01

    Commensal bacteria in the intestine play an important role in the development of immune response. These bacteria interact with cells of the gut-associated lymphoid tissues (GALT). Among cells of the GALT, B-1 cells are of note. These cells are involved in the production of natural antibodies. In the present study, we determined whether manipulation of the intestinal microbiota by administration of probiotics, which we had previously shown to enhance specific systemic antibody response, could affect the development of natural antibodies in the intestines and sera of chickens. Our findings demonstrate that when 1-day-old chicks were treated with probiotics, serum and intestinal antibodies reactive to tetanus toxoid (TT) and Clostridium perfringens alpha-toxin in addition to intestinal immunoglobulin A (IgA) reactive to bovine serum albumin (BSA) were increased in unimmunized chickens. Moreover, IgG antibodies reactive to TT were increased in the intestines of probiotic-treated chickens compared to those of untreated controls. In serum, IgG and IgM reactive to TT and alpha-toxin were increased in probiotic-treated, unimmunized chickens compared to levels in untreated controls. However, no significant difference in serum levels of IgM or IgG response to BSA was observed. These results are suggestive of the induction of natural antibodies in probiotic-treated, unimmunized chickens. Elucidating the role of these antibodies in maintenance of the chicken immune system homeostasis and immune response to pathogens requires further investigation.

  15. Diverse Natural Products from Dichlorocyclobutanones: An Evolutionary Tale.

    Science.gov (United States)

    Deprés, Jean-Pierre; Delair, Philippe; Poisson, Jean-François; Kanazawa, Alice; Greene, Andrew E

    2016-02-16

    11-Nor PGE2 was prepared in our laboratory several years ago and used to obtain the corresponding ring-expanded γ-butyrolactam, γ-butyrolactone, and cyclopentanone derivatives. The conversion of a cyclobutanone into a cyclopentanone had relatively little precedent and merited further study. It was soon found that the presence of a single chlorine adjacent to the carbonyl not only greatly accelerated the reaction with ethereal diazomethane, but also substantially enhanced its regioselectivity; not surprisingly, a second chlorine further increased both. The confluence of this finding and the discovery by Krepski and Hassner that the presence of phosphorus oxychloride significantly improved the Zn-mediated dehalogenation procedure for the preparation of α,α-dichlorocyclobutanones from olefins provided the starting point for decades' worth of exciting adventures in natural product synthesis. A wide variety of naturally occurring 5-membered carbocycles (e.g., hirsutanes, cuparenones, bakkanes, guaianolides, azulenes) could thus be prepared by using dichloroketene-olefin cycloaddition, followed by regioselective one-carbon ring expansion with diazomethane. Importantly, it was also found that natural γ-butyrolactones (e.g., β-oxygenated γ-butyrolactones, lactone fatty acids) could be secured through regioselective Baeyer-Villiger oxidation of cycloadducts with m-CPBA and that naturally occurring γ-butyrolactam derivatives (e.g., amino acids, pyrrolidines, pyrrolizidines, indolizidines) could be efficiently obtained by regioselective Beckmann ring expansion of the adducts with O-(mesitylenesulfonyl)hydroxylamine (Tamura's reagent). These 5-membered carbocycles, γ-butyrolactones, and γ-butyrolactam derivatives were generally secured in enantiopure form through the use of either intrinsically chiral olefins or olefins bearing Stericol, a highly effective chiral auxiliary developed specifically for this "three-atom olefin annelation" approach. In addition

  16. Evolution of polyploid triticum wheats under cultivation: the role of domestication, natural hybridization and allopolyploid speciation in their diversification.

    Science.gov (United States)

    Matsuoka, Yoshihiro

    2011-05-01

    The evolution of the polyploid Triticum wheats is distinctive in that domestication, natural hybridization and allopolyploid speciation have all had significant impacts on their diversification. In this review, I outline the phylogenetic relationships of cultivated wheats and their wild relatives and provide an overview of the recent progress and remaining issues in understanding the genetic and ecological factors that favored their evolution. An attempt is made to view the evolution of the polyploid Triticum wheats as a continuous process of diversification that was initiated by domestication of tetraploid emmer wheat and driven by various natural events ranging from interploidy introgression via hybridization to allopolyploid speciation of hexaploid common wheat, instead of viewing it as a group of discrete evolutionary processes that separately proceeded at the tetraploid and hexaploid levels. This standpoint underscores the important role of natural hybridization in the reticulate diversification of the tetraploid-hexaploid Triticum wheat complex and highlights critical, but underappreciated, issues that concern the allopolyploid speciation of common wheat.

  17. Lichen symbiosis: nature's high yielding machines for induced hydrogen production.

    Science.gov (United States)

    Papazi, Aikaterini; Kastanaki, Elizabeth; Pirintsos, Stergios; Kotzabasis, Kiriakos

    2015-01-01

    Hydrogen is a promising future energy source. Although the ability of green algae to produce hydrogen has long been recognized (since 1939) and several biotechnological applications have been attempted, the greatest obstacle, being the O2-sensitivity of the hydrogenase enzyme, has not yet been overcome. In the present contribution, 75 years after the first report on algal hydrogen production, taking advantage of a natural mechanism of oxygen balance, we demonstrate high hydrogen yields by lichens. Lichens have been selected as the ideal organisms in nature for hydrogen production, since they consist of a mycobiont and a photobiont in symbiosis. It has been hypothesized that the mycobiont's and photobiont's consumption of oxygen (increase of COX and AOX proteins of mitochondrial respiratory pathways and PTOX protein of chrolorespiration) establishes the required anoxic conditions for the activation of the phycobiont's hydrogenase in a closed system. Our results clearly supported the above hypothesis, showing that lichens have the ability to activate appropriate bioenergetic pathways depending on the specific incubation conditions. Under light conditions, they successfully use the PSII-dependent and the PSII-independent pathways (decrease of D1 protein and parallel increase of PSaA protein) to transfer electrons to hydrogenase, while under dark conditions, lichens use the PFOR enzyme and the dark fermentative pathway to supply electrons to hydrogenase. These advantages of lichen symbiosis in combination with their ability to survive in extreme environments (while in a dry state) constitute them as unique and valuable hydrogen producing natural factories and pave the way for future biotechnological applications.

  18. Lichen symbiosis: nature's high yielding machines for induced hydrogen production.

    Directory of Open Access Journals (Sweden)

    Aikaterini Papazi

    Full Text Available Hydrogen is a promising future energy source. Although the ability of green algae to produce hydrogen has long been recognized (since 1939 and several biotechnological applications have been attempted, the greatest obstacle, being the O2-sensitivity of the hydrogenase enzyme, has not yet been overcome. In the present contribution, 75 years after the first report on algal hydrogen production, taking advantage of a natural mechanism of oxygen balance, we demonstrate high hydrogen yields by lichens. Lichens have been selected as the ideal organisms in nature for hydrogen production, since they consist of a mycobiont and a photobiont in symbiosis. It has been hypothesized that the mycobiont's and photobiont's consumption of oxygen (increase of COX and AOX proteins of mitochondrial respiratory pathways and PTOX protein of chrolorespiration establishes the required anoxic conditions for the activation of the phycobiont's hydrogenase in a closed system. Our results clearly supported the above hypothesis, showing that lichens have the ability to activate appropriate bioenergetic pathways depending on the specific incubation conditions. Under light conditions, they successfully use the PSII-dependent and the PSII-independent pathways (decrease of D1 protein and parallel increase of PSaA protein to transfer electrons to hydrogenase, while under dark conditions, lichens use the PFOR enzyme and the dark fermentative pathway to supply electrons to hydrogenase. These advantages of lichen symbiosis in combination with their ability to survive in extreme environments (while in a dry state constitute them as unique and valuable hydrogen producing natural factories and pave the way for future biotechnological applications.

  19. Lichen Symbiosis: Nature's High Yielding Machines for Induced Hydrogen Production

    Science.gov (United States)

    Papazi, Aikaterini; Kastanaki, Elizabeth; Pirintsos, Stergios; Kotzabasis, Kiriakos

    2015-01-01

    Hydrogen is a promising future energy source. Although the ability of green algae to produce hydrogen has long been recognized (since 1939) and several biotechnological applications have been attempted, the greatest obstacle, being the O2-sensitivity of the hydrogenase enzyme, has not yet been overcome. In the present contribution, 75 years after the first report on algal hydrogen production, taking advantage of a natural mechanism of oxygen balance, we demonstrate high hydrogen yields by lichens. Lichens have been selected as the ideal organisms in nature for hydrogen production, since they consist of a mycobiont and a photobiont in symbiosis. It has been hypothesized that the mycobiont’s and photobiont’s consumption of oxygen (increase of COX and AOX proteins of mitochondrial respiratory pathways and PTOX protein of chrolorespiration) establishes the required anoxic conditions for the activation of the phycobiont’s hydrogenase in a closed system. Our results clearly supported the above hypothesis, showing that lichens have the ability to activate appropriate bioenergetic pathways depending on the specific incubation conditions. Under light conditions, they successfully use the PSII-dependent and the PSII-independent pathways (decrease of D1 protein and parallel increase of PSaA protein) to transfer electrons to hydrogenase, while under dark conditions, lichens use the PFOR enzyme and the dark fermentative pathway to supply electrons to hydrogenase. These advantages of lichen symbiosis in combination with their ability to survive in extreme environments (while in a dry state) constitute them as unique and valuable hydrogen producing natural factories and pave the way for future biotechnological applications. PMID:25826211

  20. Dynamics of Rex3 in the genomes of endangered Iberian Leuciscinae (Teleostei, Cyprinidae and their natural hybrids

    Directory of Open Access Journals (Sweden)

    Carla Sofia A. Pereira

    2015-10-01

    Full Text Available Iberian Leuciscinae are greatly diverse comprising taxa of hybrid origin. With highly conservative karyotypes, Iberian Chondrostoma s.l. have recently demonstrated sub-chromosomal differentiation and rapid genome restructuring in natural hybrids, which was confirmed by ribosomal DNA (rDNA transposition and/or multiplication. To understand the role of repetitive DNAs in the differentiation of their genomes, a genetic and molecular cytogenetic survey was conducted in Achondrostoma oligolepis, Anaecypris hispanica, Iberochondrostoma lemmingii, I. lusitanicum, Pseudochondrostoma duriense, P. polylepis, Squalius pyrenaicus and hybrids between A. oligolepis x (P. duriense/P. polylepis, which represent 'alburnine', chondrostomine and Squalius lineages. The chromosomal distribution of Rex3 retroelement was found highly compartmentalized at centromeres and moderately at telomeres, co-localizing with 5S rDNA loci, and grossly correlating with heterochromatin and blocks of C0t-1 DNA. This accumulation was evident in at least 10 chromosome pairs, a pattern that seemed to be shared among the different species, likely predating their divergence. Nevertheless, species-specific clusters were detected in I. lusitanicum, P. duriense, P. polylepis and S. pyrenaicus demonstrating rapid and independent differentiation. Natural hybrids followed the same accumulation pattern and association with repetitive sequences but with increased number of Rex3 clusters and correlating with translocated 45S rDNA clusters. Rex3 sequence phylogeny didn't agree with its hosts' phylogeny but the observed distribution pattern is congruent with an evolutionary tendency to protect its activity, a robust regulatory system and/or events of horizontal transfer. This is the first report of retroelement physical mapping in Cyprinidae. It helped outlining conceivable ancestral homologies and recognizing retrotransposon activation in hybrids, being possibly associated with genome

  1. NATURAL ANTIOXIDANT INGREDIENT FROM BY-PRODUCTS OF FRUITS

    Directory of Open Access Journals (Sweden)

    G. S. El-Baroty

    2014-01-01

    used safely in the edible oil industry and cosmetics to delay its oxidation. It can be applied in other food industries as a natural antioxidant instead of synthetic antioxidants. Further study should be carried out to identify the predominant phenolics responsible for the antioxidant activity of by product extracts.

  2. Production of substitute natural gas by biomass hydrogasification

    Energy Technology Data Exchange (ETDEWEB)

    Mozaffarian, M.; Zwart, R.W.R. [ECN Biomass, Petten (Netherlands)

    2000-11-01

    Hydrogen, generated from renewable sources, is likely to play a major role in the future energy supply. The storage and transport of hydrogen can take place in its free form (H2), or chemically bound, e.g. as methane. However, the storage and transport of hydrogen in its free form are more complex, and probably would require more energy than the storage and transport of hydrogen in chemical form. An additional important advantage of the indirect use of hydrogen as energy carrier is, that in the future renewable energy supply, pads of the existing large-scale energy infra- structure could still be used. Production of Substitute Natural Gas (SNG) by biomass hydrogasification has been assessed as a process for chemical storage of hydrogen. Thermodynamic analysis has shown the feasibility of this process. The product gas of the process has a Wobbe-index, a mole percentage methane, and a calorific value quite comparable to the quality of the Dutch natural gas. With a hydrogen content below 10 mol%, the produced SNG can be transported through the existing gas net without any additional adjustment. The integrated system has an energetic efficiency of 81% (LHV). In the long term, the required hydrogen for this process can be produced by water electrolysis, with electricity from renewable sources. In the short term, hydrogen may be obtained from hydrogen-rich gases available as by-product from industrial processes. Results of thermodynamic analysis of the process and experimental work, application potentials of the process in the Netherlands, and plans for future development are presented. 21 refs.

  3. Natural Product Research in the Australian Marine Invertebrate Dicathais orbita

    Directory of Open Access Journals (Sweden)

    Kirsten Benkendorff

    2013-04-01

    Full Text Available The predatory marine gastropod Dicathais orbita has been the subject of a significant amount of biological and chemical research over the past five decades. Natural products research on D. orbita includes the isolation and identification of brominated indoles and choline esters as precursors of Tyrian purple, as well as the synthesis of structural analogues, bioactivity testing, biodistributional and biosynthetic studies. Here I also report on how well these compounds conform to Lipinski’s rule of five for druglikeness and their predicted receptor binding and enzyme inhibitor activity. The composition of mycosporine-like amino acids, fatty acids and sterols has also been described in the egg masses of D. orbita. The combination of bioactive compounds produced by D. orbita is of interest for further studies in chemical ecology, as well as for future nutraceutical development. Biological insights into the life history of this species, as well as ongoing research on the gene expression, microbial symbionts and biosynthetic capabilities, should facilitate sustainable production of the bioactive compounds. Knowledge of the phylogeny of D. orbita provides an excellent platform for novel research into the evolution of brominated secondary metabolites in marine molluscs. The range of polarities in the brominated indoles produced by D. orbita has also provided an effective model system used to develop a new method for biodistributional studies. The well characterized suite of chemical reactions that generate Tyrian purple, coupled with an in depth knowledge of the ecology, anatomy and genetics of D. orbita provide a good foundation for ongoing natural products research.

  4. Hybridization among three native North American Canis species in a region of natural sympatry.

    Directory of Open Access Journals (Sweden)

    Frank Hailer

    Full Text Available BACKGROUND: Population densities of many species throughout the world are changing due to direct persecution as well as anthropogenic habitat modification. These changes may induce or increase the frequency of hybridization among taxa. If extensive, hybridization can threaten the genetic integrity or survival of endangered species. Three native species of the genus Canis, coyote (C. latrans, Mexican wolf (C. lupus baileyi and red wolf (C. rufus, were historically sympatric in Texas, United States. Human impacts caused the latter two to go extinct in the wild, although they survived in captive breeding programs. Morphological data demonstrate historic reproductive isolation between all three taxa. While the red wolf population was impacted by introgressive hybridization with coyotes as it went extinct in the wild, the impact of hybridization on the Texas populations of the other species is not clear. METHODOLOGY/ PRINCIPAL FINDINGS: We surveyed variation at maternally and paternally inherited genetic markers (mitochondrial control region sequence and Y chromosome microsatellites in coyotes from Texas, Mexican wolves and red wolves from the captive breeding programs, and a reference population of coyotes from outside the historic red wolf range. Levels of variation and phylogenetic analyses suggest that hybridization has occasionally taken place between all three species, but that the impact on the coyote population is very small. CONCLUSION/SIGNIFICANCE: Our results demonstrate that the factors driving introgressive hybridization in sympatric Texan Canis are multiple and complex. Hybridization is not solely determined by body size or sex, and density-dependent effects do not fully explain the observed pattern either. No evidence of hybridization was identified in the Mexican wolf captive breeding program, but introgression appears to have had a greater impact on the captive red wolves.

  5. Biodiesel production by using lipase immobilized onto novel silica-based hybrid foams

    Energy Technology Data Exchange (ETDEWEB)

    Brun, Nicolas [Centre de Recherche Paul Pascal, Pessac (France); Institut des Sciences Moleculaires, Talence (France); Garcia, Annick Babeau; Oestreicher, Victor; Durand, Fabien; Backov, Renal [Centre de Recherche Paul Pascal, Pessac (France); Deleuze, Herve [Institut des Sciences Moleculaires, Talence (France); Laurent, Guillaume; Sanchez, Clement [Laboratoire de Chimie de la Matiere Condensee, Paris (France)

    2010-07-01

    The covalent immobilization of crude lipases within silica-based macroporous frameworks have been performed by combining sol-gel process, concentrated direct emulsion, lyotropic mesophase and post-synthesis functionalizations. The assynthesized open cell hybrid monoliths exhibit high macroscopic porosity, around 90%, providing interconnected scaffold while reducing the diffusion low kinetic issue. The entrapment of enzymes in such foams deals with a high stability over esterification of fatty acids, hydrolysis of triglycerides (not shown herein) and biodiesel production by transesterification. (orig.)

  6. Modelling Beam Dynamics and RF Production in Two Beam Accelerators with a Hybrid Simulation Tool

    Science.gov (United States)

    Lidia, Steven

    2000-04-01

    A hybrid mapping and PIC code is described and applied to the study of transient-to-steady-state phenomena of beam dynamics and rf power production in relativistic-klystron two-beam accelerators. Beam and beamline parameters appropriate to a single device that produces 40-100 MW per meter over 10 meters with a 120 ns pulse length are described and used.

  7. Use of 2n gametes for the production of sexual polyploids from sterile Oriental x Asiatic hybrids of lilies (Lilium)

    NARCIS (Netherlands)

    Barba Gonzalez, R.; Lokker, A.C.; Lim Ki-Byung,; Ramanna, M.S.; Tuyl, van J.M.

    2004-01-01

    Sixteen Oriental and 12 Asiatic cultivars were crossed in 158 different combinations. A total of 708 F1 hybrids were obtained from 86 of the different combinations of 15 Oriental and 11 Asiatic cultivars. Because the Lilium cultivars (2n=2x=24) used for the production of these hybrids belong to two

  8. Occurrence of aflatoxin B1 in natural products

    Directory of Open Access Journals (Sweden)

    Guilherme Prado

    2012-12-01

    Full Text Available The media claims for the consumption of natural resource-based food have gradually increased in both developing and developed countries. The interest in the safety of these products is partially due to the possible presence of toxigenic fungi acting as mycotoxin producers, such as aflatoxins produced during the secondary metabolism of Aspergillus flavus, A. parasiticus and A. nomius. Aflatoxins, mainly aflatoxin B1, are directly associated with liver cancer in human beings. This paper is aimed at evaluating the presence of aflatoxin B1 in a few vegetable drugs, dried plant extracts and industrialized products traded in 2010 in the city of Belo Horizonte, State of Minas Gerais, Brazil. The method used for the quantification of aflatoxin B1 was based on extraction through acetone:water (85:15, immunoaffinity column purification followed by separation and detection in high efficiency liquid chromatography. Under the conditions of analysis, the Limits of Detection and Quantification were 0.6 µg kg-1 and 1.0 µg kg-1respectively. The complete sets of analyses were carried out in duplicate. Aflatoxin B1 was noticed in a single sample (< 1.0 µg kg-1. The results revealed low aflatoxin B1contamination in the products under analysis. However, it is required to establish a broad monitoring program in order to obtain additional data and check up on the actual extension of contamination.

  9. Production of CaCO3/hyperbranched polyglycidol hybrid films using spray-coating technique.

    Science.gov (United States)

    Malinova, Kalina; Gunesch, Manfred; Montero Pancera, Sabrina; Wengeler, Robert; Rieger, Bernhard; Volkmer, Dirk

    2012-05-15

    Biomineralizing organisms employ macromolecules and cellular processing strategies in order to produce highly complex composite materials such as nacre. Bionic approaches translating this knowledge into viable technical production schemes for a large-scale production of biomimetic hybrid materials have met with limited success so far. Investigations presented here thus focus on the production of CaCO(3)/polymer hybrid coatings that can be applied to huge surface areas via reactive spray-coating. Technical requirements for simplicity and cost efficiency include a straightforward one-pot synthesis of low molecular weight hyperbranched polyglycidols (polyethers of 2,3-epoxy-1-propanol) as a simple mimic of biological macromolecules. Polymers functionalized with phosphate monoester, sulfate or carboxylate groups provide a means of controlling CaCO(3) particle density and morphology in the final coatings. We employ reactive spray-coating techniques to generate CaCO(3)/hybrid coatings among which vaterite composites can be prepared in the presence of sulfate-containing hyperbranched polyglycidol. These coatings show high stability and remained unchanged for periods longer than 9 months. By employing carboxylate-based hyperbranched polyglycidol, it is possible to deposit vaterite-calcite composites, whereas phosphate-ester-based hyperbranched polyglycidol leads to calcite composites. Nanoindentation was used to study mechanical properties, showing that coatings thus obtained are slightly harder than pure calcite. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Natural gas productive capacity for the lower 48 states 1985 through 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    This publication presents information on wellhead productive capacity and a projection of gas production requirements. A history of natural gas production and productive capacity at the wellhead, along with a projection of the same, is illustrated.

  11. Hybrid Baryons

    CERN Document Server

    Page, P R

    2003-01-01

    We review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modelled by both the bag and flux-tube models. The low-lying hybrid baryon is N 1/2^+ with a mass of 1.5-1.8 GeV. Hybrid baryons can be produced in the glue-rich processes of diffractive gamma N and pi N production, Psi decays and p pbar annihilation.

  12. Synthetic biology for production of natural and new-to-nature terpenoids in photosynthetic organisms.

    Science.gov (United States)

    Arendt, Philipp; Pollier, Jacob; Callewaert, Nico; Goossens, Alain

    2016-07-01

    With tens of thousands of characterized members, terpenoids constitute the largest class of natural compounds that are synthesized by all living organisms. Several terpenoids play primary roles in the maintenance of cell membrane fluidity, as pigments or as phytohormones, but most of them function as specialized metabolites that are involved in plant resistance to herbivores or plant-environment interactions. Terpenoids are an essential component of human nutrition, and many are economically important pharmaceuticals, aromatics and potential next-generation biofuels. Because of the often low abundance in their natural source, as well as the demand for novel terpenoid structures with new or improved bioactivities, terpenoid biosynthesis has become a prime target for metabolic engineering and synthetic biology projects. In this review we focus on the creation of new-to-nature or tailor-made plant-derived terpenoids in photosynthetic organisms, in particular by means of combinatorial biosynthesis and the activation of silent metabolism. We reflect on the characteristics of different potential photosynthetic host organisms and recent advances in synthetic biology and discuss their utility for the (heterologous) production of (novel) terpenoids.

  13. Diallel analysis of popcorn lines and hybrids for baby corn production

    Directory of Open Access Journals (Sweden)

    Lucas Rafael de Souza Camacho

    2015-03-01

    Full Text Available The aim of this study was to evaluate the combining ability of popcorn lines and hybrids with favorable traits for baby corn production, using lines extracted from the major genotypes of the Brazilian germplasm. From nine popcorn lines, derived from the genotypes Zélia, CMS 42, CMS 43, UEM M2, Zaeli and IAC 112, 36 single-cross hybrids were obtained without reciprocals. In partial diallel crosses, 25 single-cross hybrids were obtained, derived from crosses of five lines of the Zaeli (group I with five lines from IAC 112 (group II. We recommend using lines derived from Zaeli and CMS 42 in hybrid breeding programs for higher ear yields. The lines P9.5.1 and P9.5.5 (group I and P8.3 and P8.5 (group II can be recommended for recombination within each group and for the formation of two synthetic populations for recurrent selection, in order to increase ear yield.

  14. Biomass production of hybrid aspen growing on former farm land in Sweden

    Institute of Scientific and Technical Information of China (English)

    Tord Johansson

    2013-01-01

    We construct dry weight equations for hybrid aspen growing on former farmland in Sweden.Dry weight equations for fractions of hybrid aspen trees were also made.We estimated biomass production in 24 stands.The stands were located in Sweden at latitudes ranging from 55 to 60° N.The mean age was 18 years (range 15-23),the mean stand density 1090 stems·ha-1 (range 378-2374),and the mean diameter at breast height (over bark) 178 mm (range 85-244 mm).Soil types in the hybrid aspen stands were mainly clay (21 stands),tills (2 stands) and other (1 stand).The mean total standing dry weight above stump level (≈200 mm) for the hybrid aspen stands was 135±53 t·ha-1 with a range of 42-219 t·ha-1.In addition to estimating conventional dry weights of trees and tree components,basic density,specific leaf area (SLA),projected leaf area (PLA) and leaf area index (LAI) were estimated and were in agreement with published figures.

  15. Inhibitors of Microglial Neurotoxicity: Focus on Natural Products

    Directory of Open Access Journals (Sweden)

    Kyoungho Suk

    2011-01-01

    Full Text Available Microglial cells play a dual role in the central nervous system as they have both neurotoxic and neuroprotective effects. Uncontrolled and excessive activation of microglia often contributes to inflammation-mediated neurodegeneration. Recently, much attention has been paid to therapeutic strategies aimed at inhibiting neurotoxic microglial activation. Pharmacological inhibitors of microglial activation are emerging as a result of such endeavors. In this review, natural products-based inhibitors of microglial activation will be reviewed. Potential neuroprotective activity of these compounds will also be discussed. Future works should focus on the discovery of novel drug targets that specifically mediate microglial neurotoxicity rather than neuroprotection. Development of new drugs based on these targets may require a better understanding of microglial biology and neuroinflammation at the molecular, cellular, and systems levels.

  16. Deoxygedunin, a natural product with potent neurotrophic activity in mice.

    Directory of Open Access Journals (Sweden)

    Sung-Wuk Jang

    Full Text Available Gedunin, a family of natural products from the Indian neem tree, possess a variety of biological activities. Here we report the discovery of deoxygedunin, which activates the mouse TrkB receptor and its downstream signaling cascades. Deoxygedunin is orally available and activates TrkB in mouse brain in a BDNF-independent way. Strikingly, it prevents the degeneration of vestibular ganglion in BDNF -/- pups. Moreover, deoxygedunin robustly protects rat neurons from cell death in a TrkB-dependent manner. Further, administration of deoxygedunin into mice displays potent neuroprotective, anti-depressant and learning enhancement effects, all of which are mediated by the TrkB receptor. Hence, deoxygedunin imitates BDNF's biological activities through activating TrkB, providing a powerful therapeutic tool for treatment of various neurological diseases.

  17. The Complexity of Bioactive Natural Products in Plants

    DEFF Research Database (Denmark)

    Frisch, Tina

    Plants produce a diverse range of bioactive natural products promoting their fitness. These specialized metabolites may serve as chemical defence against herbivores and pathogens and may inhibit the growth and development of competing species. Hydroxynitrile glucosides and glucosinolates are two...... classes of defence compounds, which have diverging properties, but also share common biosynthetic features. Hydroxynitrile glucosides are produced in species across the plant kingdom, whereas glucosinolates are found almost exclusively within the Brassicales, which generally does not contain...... these two plant species interesting gateways for addressing these questions of evolution. The presented research demonstrates that the biosynthetic pathway for the hydroxynitrile glucoside alliarinoside in A. petiolata does not follow the general scheme for hydroxynitrile glucoside biosynthesis in other...

  18. Marine Natural Products from New Caledonia--A Review.

    Science.gov (United States)

    Motuhi, Sofia-Eléna; Mehiri, Mohamed; Payri, Claude Elisabeth; La Barre, Stéphane; Bach, Stéphane

    2016-03-16

    Marine micro- and macroorganisms are well known to produce metabolites with high biotechnological potential. Nearly 40 years of systematic prospecting all around the New Caledonia archipelago and several successive research programs have uncovered new chemical leads from benthic and planktonic organisms. After species identification, biological and/or pharmaceutical analyses are performed on marine organisms to assess their bioactivities. A total of 3582 genera, 1107 families and 9372 species have been surveyed and more than 350 novel molecular structures have been identified. Along with their bioactivities that hold promise for therapeutic applications, most of these molecules are also potentially useful for cosmetics and food biotechnology. This review highlights the tremendous marine diversity in New Caledonia, and offers an outline of the vast possibilities for natural products, especially in the interest of pursuing collaborative fundamental research programs and developing local biotechnology programs.

  19. Natural products in medicine: transformational outcome of synthetic chemistry.

    Science.gov (United States)

    Szychowski, Janek; Truchon, Jean-François; Bennani, Youssef L

    2014-11-26

    This review brings to the forefront key synthetic modifications on natural products (NPs) that have yielded successful drugs. The emphasis is placed on the power of targeted chemical transformations in enhancing the therapeutic value of NPs through optimization of pharmacokinetics, stability, potency, and/or selectivity. Multiple classes of NPs such as macrolides, opioids, steroids, and β-lactams used to treat a variety of conditions such as cancers, infections, inflammation are exemplified. Molecular modeling or X-ray structures of NP/protein complexes supporting the observed boost in therapeutic value of the modified NPs are also discussed. Significant advancement in synthetic chemistry, in structure determination, and in the understanding of factors controlling pharmacokinetics can now better position drug discovery teams to undertake NPs as valuable leads. We hope that the beneficial NPs synthetic modifications outlined here will reignite medicinal chemists' interest in NPs and their derivatives.

  20. Can Invalid Bioactives Undermine Natural Product-Based Drug Discovery?

    Science.gov (United States)

    2015-01-01

    High-throughput biology has contributed a wealth of data on chemicals, including natural products (NPs). Recently, attention was drawn to certain, predominantly synthetic, compounds that are responsible for disproportionate percentages of hits but are false actives. Spurious bioassay interference led to their designation as pan-assay interference compounds (PAINS). NPs lack comparable scrutiny, which this study aims to rectify. Systematic mining of 80+ years of the phytochemistry and biology literature, using the NAPRALERT database, revealed that only 39 compounds represent the NPs most reported by occurrence, activity, and distinct activity. Over 50% are not explained by phenomena known for synthetic libraries, and all had manifold ascribed bioactivities, designating them as invalid metabolic panaceas (IMPs). Cumulative distributions of ∼200,000 NPs uncovered that NP research follows power-law characteristics typical for behavioral phenomena. Projection into occurrence–bioactivity–effort space produces the hyperbolic black hole of NPs, where IMPs populate the high-effort base. PMID:26505758

  1. Structure Determination of Natural Products by Nuclear Magnetic Resonance Spectroscopy

    Science.gov (United States)

    Li, Du.

    High-field NMR experiments were used to determine the full structures of six new natural products extracted from plants. These are: four saponins (PT-2, P1, P2 and P3) from the plant Alphitonia zizyphoides found in Samoa; one sesquiterpene (DF-4) from Douglas fir and one diterpene derivative (E-2) from a Chinese medicinal herb. By concerted use of various 1D and 2D NMR techniques, the structures of the above compounds were established and complete resonance assignments were achieved. The 2D INADEQUATE technique coupled with a computerized spectral analysis was extensively used. When carried out on concentrations as low as 60 mg of sample, this technique provided absolute confirmation of the assignments for 35 of the possible 53 C-C bonds for PT-2. On 30 mg of sample of E-21, it revealed 22 of 28 possible C-C bonds.

  2. Marine Natural Products from New Caledonia—A Review

    Directory of Open Access Journals (Sweden)

    Sofia-Eléna Motuhi

    2016-03-01

    Full Text Available Marine micro- and macroorganisms are well known to produce metabolites with high biotechnological potential. Nearly 40 years of systematic prospecting all around the New Caledonia archipelago and several successive research programs have uncovered new chemical leads from benthic and planktonic organisms. After species identification, biological and/or pharmaceutical analyses are performed on marine organisms to assess their bioactivities. A total of 3582 genera, 1107 families and 9372 species have been surveyed and more than 350 novel molecular structures have been identified. Along with their bioactivities that hold promise for therapeutic applications, most of these molecules are also potentially useful for cosmetics and food biotechnology. This review highlights the tremendous marine diversity in New Caledonia, and offers an outline of the vast possibilities for natural products, especially in the interest of pursuing collaborative fundamental research programs and developing local biotechnology programs.

  3. Molecular identification and histopathological study of natural Streptococcus agalactiae infection in hybrid tilapia (Oreochromis niloticus)

    Science.gov (United States)

    Laith, AA; Ambak, Mohd Azmi; Hassan, Marina; Sheriff, Shahreza Md.; Nadirah, Musa; Draman, Ahmad Shuhaimi; Wahab, Wahidah; Ibrahim, Wan Nurhafizah Wan; Aznan, Alia Syafiqah; Jabar, Amina; Najiah, Musa

    2017-01-01

    Aim: The main objective of this study was to emphasize on histopathological examinations and molecular identification of Streptococcus agalactiae isolated from natural infections in hybrid tilapia (Oreochromis niloticus) in Temerloh Pahang, Malaysia, as well as to determine the susceptibility of the pathogen strains to various currently available antimicrobial agents. Materials and Methods: The diseased fishes were observed for variable clinical signs including fin hemorrhages, alterations in behavior associated with erratic swimming, exophthalmia, and mortality. Tissue samples from the eyes, brain, kidney, liver, and spleen were taken for bacterial isolation. Identification of S. agalactiae was screened by biochemical methods and confirmed by VITEK 2 and 16S rRNA gene sequencing. The antibiogram profiling of the isolate was tested against 18 standard antibiotics included nitrofurantoin, flumequine, florfenicol, amoxylin, doxycycline, oleandomycin, tetracycline, ampicillin, lincomycin, colistin sulfate, oxolinic acid, novobiocin, spiramycin, erythromycin, fosfomycin, neomycin, gentamycin, and polymyxin B. The histopathological analysis of eyes, brain, liver, kidney, and spleen was observed for abnormalities related to S. agalactiae infection. Results: The suspected colonies of S. agalactiae identified by biochemical methods was observed as Gram-positive chained cocci, β-hemolytic, and non-motile. The isolate was confirmed as S. agalactiae by VITEK 2 (99% similarity), reconfirmed by 16S rRNA gene sequencing (99% similarity) and deposited in GenBank with accession no. KT869025. The isolate was observed to be resistance to neomycin and gentamicin. The most consistent gross findings were marked hemorrhages, erosions of caudal fin, and exophthalmos. Microscopic examination confirmed the presence of marked congestion and infiltration of inflammatory cell in the eye, brain, kidney, liver, and spleen. Eye samples showed damage of the lens capsule, hyperemic and

  4. Implementation of Contract Hybrid Concept in Multi Services Products (Aplication of the Warranty Bank Products/Kafalah in Syariah Banks

    Directory of Open Access Journals (Sweden)

    Muhammad Firmansyah

    2016-08-01

    Full Text Available Product of multi services in sharia banks presented in order to meet the needs of society as well as the development of the era transactions that course in accordance with Islamic principles, then the ownership  in  the syariah products  including  multi  product  in  Islamic banking  services  using  the concept of multi akad therein. This is done so that innovation in Islamic banking products had been developed so that it can be chosen by the public in conducting business transactions. Likewise, the multi-service bank guarantee products in Islamic banking, is a multi product contract, where there is more than one contract. Bank guarantees in Islamic banking is generally called kafalah product because this product is Kafalah main contract, followed by Ijarah contract, wadiah, and qardh. This paper  examines  the  concept  of  multi-contract/contract executed  hybrid  shariah  banking  at  bank product warranty/kafalah

  5. Temperature effects on fish production across a natural thermal gradient.

    Science.gov (United States)

    O'Gorman, Eoin J; Ólafsson, Ólafur P; Demars, Benoît O L; Friberg, Nikolai; Guðbergsson, Guðni; Hannesdóttir, Elísabet R; Jackson, Michelle C; Johansson, Liselotte S; McLaughlin, Órla B; Ólafsson, Jón S; Woodward, Guy; Gíslason, Gísli M

    2016-09-01

    Global warming is widely predicted to reduce the biomass production of top predators, or even result in species loss. Several exceptions to this expectation have been identified, however, and it is vital that we understand the underlying mechanisms if we are to improve our ability to predict future trends. Here, we used a natural warming experiment in Iceland and quantitative theoretical predictions to investigate the success of brown trout as top predators across a stream temperature gradient (4-25 °C). Brown trout are at the northern limit of their geographic distribution in this system, with ambient stream temperatures below their optimum for maximal growth, and above it in the warmest streams. A five-month mark-recapture study revealed that population abundance, biomass, growth rate, and production of trout all increased with stream temperature. We identified two mechanisms that contributed to these responses: (1) trout became more selective in their diet as stream temperature increased, feeding higher in the food web and increasing in trophic position; and (2) trophic transfer through the food web was more efficient in the warmer streams. We found little evidence to support a third potential mechanism: that external subsidies would play a more important role in the diet of trout with increasing stream temperature. Resource availability was also amplified through the trophic levels with warming, as predicted by metabolic theory in nutrient-replete systems. These results highlight circumstances in which top predators can thrive in warmer environments and contribute to our knowledge of warming impacts on natural communities and ecosystem functioning.

  6. A novel male sterility-fertility restoration system in plants for hybrid seed production

    Science.gov (United States)

    Singh, Surendra Pratap; Singh, Sudhir P.; Pandey, Tripti; Singh, Ram Rakshpal; Sawant, Samir V.

    2015-01-01

    Hybrid seeds are used for stimulated crop production, as they harness heterosis. The achievement of complete male-sterility in the female-parent and the restored-fertility in F1-hybrids are the major bottlenecks in the commercial hybrid seed production. Here, we report a male sterility–fertility restoration system by engineering the inmost nutritive anther wall layer tapetum of female and male parents. In the female parent, high–level, and stringent expression of Arabidopsis autophagy–related gene BECLIN1 was achieved in the tapetum, which altered the tapetal degeneration program, leading to male sterility. This works on our previously demonstrated expression cassette based on functional complementation of TATA-box mutant (TGTA) promoter and TATA-binding protein mutant3 (TBPm3), with modification by conjugating Long Hypocotyle in Far-Red1 fragment (HFR1NT131) with TBPm3 (HFR1NT131-TBPm3) to exercise regulatory control over it. In the male parent, tapetum–specific Constitutive photo-morphogenesis1 (COP1) was expressed. The F1 obtained by crossing these engineered parents showed decreased BECLIN1 expression, which was further completely abolished when COP1-mutant (COP1L105A) was used as a male parent, leading to normal tapetal development and restored fertility. The system works on COP1-HFR1 interaction and COP1–mediated degradation of TBPm3 pool (HFR1NT131-TBPm3). The system can be deployed for hybrid seed production in agricultural crops. PMID:26073981

  7. Use of a Geothermal-Solar Hybrid Power Plant to Mitigate Declines in Geothermal Resource Productivity

    Energy Technology Data Exchange (ETDEWEB)

    Dan Wendt; Greg Mines

    2014-09-01

    Many, if not all, geothermal resources are subject to decreasing productivity manifested in the form of decreasing brine temperature, flow rate, or both during the life span of the associated power generation project. The impacts of resource productivity decline on power plant performance can be significant; a reduction in heat input to a power plant not only decreases the thermal energy available for conversion to electrical power, but also adversely impacts the power plant conversion efficiency. The reduction in power generation is directly correlated to a reduction in revenues from power sales. Further, projects with Power Purchase Agreement (PPA) contracts in place may be subject to significant economic penalties if power generation falls below the default level specified. A potential solution to restoring the performance of a power plant operating from a declining productivity geothermal resource involves the use of solar thermal energy to restore the thermal input to the geothermal power plant. There are numerous technical merits associated with a renewable geothermal-solar hybrid plant in which the two heat sources share a common power block. The geo-solar hybrid plant could provide a better match to typical electrical power demand profiles than a stand-alone geothermal plant. The hybrid plant could also eliminate the stand-alone concentrated solar power plant thermal storage requirement for operation during times of low or no solar insolation. This paper identifies hybrid plant configurations and economic conditions for which solar thermal retrofit of a geothermal power plant could improve project economics. The net present value of the concentrated solar thermal retrofit of an air-cooled binary geothermal plant is presented as functions of both solar collector array cost and electricity sales price.

  8. Biopiracy of natural products and good bioprospecting practice.

    Science.gov (United States)

    Efferth, Thomas; Banerjee, Mita; Paul, Norbert W; Abdelfatah, Sara; Arend, Joachim; Elhassan, Gihan; Hamdoun, Sami; Hamm, Rebecca; Hong, Chunlan; Kadioglu, Onat; Naß, Janine; Ochwangi, Dominic; Ooko, Edna; Ozenver, Nadire; Saeed, Mohamed E M; Schneider, Mathias; Seo, Ean-Jeong; Wu, Ching-Fen; Yan, Ge; Zeino, Maen; Zhao, Qiaoli; Abu-Darwish, Mohammad S; Andersch, Kai; Alexie, Gladys; Bessarab, Dawn; Bhakta-Guha, Dipita; Bolzani, Vanderlan; Dapat, Else; Donenko, Fedor V; Efferth, Monika; Greten, Henry J; Gunatilaka, Leslie; Hussein, Ahmed A; Karadeniz, Asuman; Khalid, Hassan E; Kuete, Victor; Lee, Ik-Soo; Liu, Liang; Midiwo, Jacob; Mora, Rodrigo; Nakagawa, Hiroshi; Ngassapa, Olipa; Noysang, Chanai; Omosa, Leonida K; Roland, Fred Hwiemtun; Shahat, Abdelaaty A; Saab, Antoine; Saeed, Elfatih M; Shan, Letian; Titinchi, Salam J J

    2016-02-15

    Biopiracy mainly focuses on the use of biological resources and/or knowledge of indigenous tribes or communities without allowing them to share the revenues generated out of economic exploitation or other non-monetary incentives associated with the resource/knowledge. Based on collaborations of scientists from five continents, we have created a communication platform to discuss not only scientific topics, but also more general issues with social relevance. This platform was termed 'PhytCancer -Phytotherapy to Fight Cancer' (www.phyt-cancer.uni-mainz.de). As a starting point, we have chosen the topic "biopiracy", since we feel this is of pragmatic significance for scientists working with medicinal plants. It was argued that the patenting of herbs or natural products by pharmaceutical corporations disregarded the ownership of the knowledge possessed by the indigenous communities on how these substances worked. Despite numerous court decisions in U.S.A. and Europe, several international treaties, (e.g. from United Nations, World Health Organization, World Trade Organization, the African Unity and others), sharing of a rational set of benefits amongst producers (mainly pharmaceutical companies) and indigenous communities is yet a distant reality. In this paper, we present an overview of the legal frameworks, discuss some exemplary cases of biopiracy and bioprospecting as excellent forms of utilization of natural resources. We suggest certain perspectives, by which we as scientists, may contribute towards prevention of biopiracy and also to foster the fair utilization of natural resources. We discuss ways, in which the interests of indigenous people especially from developing countries can be secured. Copyright © 2015 Elsevier GmbH. All rights reserved.

  9. Modulation of tumor microenvironment by chemopreventive natural products.

    Science.gov (United States)

    Park, Sin-Aye; Surh, Young-Joon

    2017-08-01

    The tumor microenvironment provides a niche in which cancer cells and their surrounding stromal cells reside and in which their interactions occur. The cross talk between cancer and stromal cells in the tumor microenvironment promotes many biological processes to support cancer cell growth, invasion, angiogenesis, and metastasis. Recently, not only cancer cells but also multiple types of surrounding stromal cells, including endothelial cells, immune cells, and fibroblasts in the tumor microenvironment, have been recognized to be attractive targets for reducing resistance to anticancer therapy and tumor recurrence. Many natural products present in fruits, vegetables, herbs, spices, and some marine organisms have been reported to inhibit, delay, or reverse multistage carcinogenesis and to inhibit the proliferation of cancerous cells and the self-renewal capacity of preexisting cancer stem-like cells. Some of these naturally occurring chemopreventive and anticarcinogenic substances can modulate the signal transduction involved in maintaining the activities/functions of stromal cells and their interactions with cancer cells within the tumor microenvironment. © 2017 New York Academy of Sciences.

  10. Culturable rare Actinomycetes: diversity, isolation and marine natural product discovery.

    Science.gov (United States)

    Subramani, Ramesh; Aalbersberg, William

    2013-11-01

    Rare Actinomycetes from underexplored marine environments are targeted in drug discovery studies due to the Actinomycetes' potentially huge resource of structurally diverse natural products with unusual biological activity. Of all marine bacteria, 10 % are Actinomycetes, which have proven an outstanding and fascinating resource for new and potent bioactive molecules. Past and present efforts in the isolation of rare Actinomycetes from underexplored diverse natural habitats have resulted in the isolation of about 220 rare Actinomycete genera of which more than 50 taxa have been reported to be the producers of 2,500 bioactive compounds. That amount represents greater than 25 % of the total Actinomycetes metabolites, demonstrating that selective isolation methods are being developed and extensively applied. Due to the high rediscovery rate of known compounds from Actinomycetes, a renewed interest in the development of new antimicrobial agents from rare and novel Actinomycetes is urgently required to combat the increasing number of multidrug-resistant human pathogens. To facilitate that discovery, this review updates all selective isolation media including pretreatment and enrichment methods for the isolation of marine rare Actinomycetes. In addition, this review demonstrates that discovering new compounds with novel scaffolds can be increased by intensive efforts in isolating and screening rare marine genera of Actinomycetes. Between 2007 and mid-2013, 80 new rare Actinomycete species were reported from marine habitats. They belong to 23 rare families, of which three are novel, and 20 novel genera. Of them, the family Micromonosporaceae is dominant as a producer of promising chemical diversity.

  11. New natural product carbonic anhydrase inhibitors incorporating phenol moieties.

    Science.gov (United States)

    Karioti, Anastasia; Ceruso, Mariangela; Carta, Fabrizio; Bilia, Anna-Rita; Supuran, Claudiu T

    2015-11-15

    Carbonic anhydrases (CAs, EC 4.2.1.1) catalyze the fundamental reaction of CO2 hydration in all living organisms, being actively involved in the regulation of a plethora of patho/physiological conditions. They represent a typical example of enzyme convergent evolution, as six genetically unrelated families of such enzymes were described so far. The need to find selective CA inhibitors (CAIs) triggered the investigation of natural product libraries, which proved to be a valid source of agents with such an activity, as demonstrated for the phenols, polyamines and coumarins. Herein we report an in vitro inhibition study of human (h) CA isoforms hCAs I, II, IV, VII and XII with a panel of natural polyphenols including flavones, flavonols, flavanones, flavanols, isoflavones and depsides, some of which extracted from Quercus ilex and Salvia miltiorrhiza. Several of the investigated derivatives showed interesting inhibition activity and selectivities for inhibiting some important isoforms over the off-target ones hCA I and II.

  12. Role of Antioxidants and Natural Products in Inflammation

    Directory of Open Access Journals (Sweden)

    Palanisamy Arulselvan

    2016-01-01

    Full Text Available Inflammation is a comprehensive array of physiological response to a foreign organism, including human pathogens, dust particles, and viruses. Inflammations are mainly divided into acute and chronic inflammation depending on various inflammatory processes and cellular mechanisms. Recent investigations have clarified that inflammation is a major factor for the progression of various chronic diseases/disorders, including diabetes, cancer, cardiovascular diseases, eye disorders, arthritis, obesity, autoimmune diseases, and inflammatory bowel disease. Free radical productions from different biological and environmental sources are due to an imbalance of natural antioxidants which further leads to various inflammatory associated diseases. In this review article, we have outlined the inflammatory process and its cellular mechanisms involved in the progression of various chronic modern human diseases. In addition, we have discussed the role of free radicals-induced tissue damage, antioxidant defence, and molecular mechanisms in chronic inflammatory diseases/disorders. The systematic knowledge regarding the role of inflammation and its associated adverse effects can provide a clear understanding in the development of innovative therapeutic targets from natural sources that are intended for suppression of various chronic inflammations associated diseases.

  13. Aminobenzoates as building blocks for natural product assembly lines.

    Science.gov (United States)

    Walsh, Christopher T; Haynes, Stuart W; Ames, Brian D

    2012-01-01

    The ortho-, meta-, and para- regioisomers of aminobenzoate are building blocks for a wide range of microbial natural products. Both the ortho-isomer (anthranilate) and PABA derive from the central shikimate pathway metabolite chorismate while the meta-isomer is not available by that route and starts from UDP-3-aminoglucose. PABA is largely funnelled into folate biosynthesis while anthranilate is the scaffold for biosynthetic elaboration into many natural heterocycles, most notably with its role in indole formation for tryptophan biosynthesis. Anthranilate is also converted to benzodiazepinones, fumiquinazolines, quinoxalines, phenoxazines, benzoxazolinates, quinolones, and phenazines, often with redox enzyme participation. The 5-hydroxy form of 3-aminobenzaote is the starter unit for ansa-bridged rifamycins, ansamitocins, and geldanamycins, whereas regioisomers 2-hydroxy, 4-hydroxy and 2,4-dihydroxy-3-aminobenzoate are key components of antimycin, grixazone, and platencin and platensimycin biosynthesis, respectively. The enzymatic mechanisms for generation of the aminobenzoate regioisomers and their subsequent utilization for diverse heterocycle and macrocycle construction are examined.

  14. Recent Trends in the Use of Natural Antioxidants for Meat and Meat Products

    National Research Council Canada - National Science Library

    Kumar, Yogesh; Yadav, Deep Narayan; Ahmad, Tanbir; Narsaiah, Kairam

    2015-01-01

    .... Thus, the food industry now chooses natural products over synthetic ones. This review provides an overview of the current trends in the use of antioxidants from natural sources, for potential applications in meat and meat products...

  15. Fingerprinting of Natural Product by Eastern Blotting Using Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Hiroyuki Tanaka

    2012-01-01

    Full Text Available We succeeded in developing the fingerprint of natural product by eastern blotting using monoclonal antibodies. After developing and separating them on a TLC plate, solasodine glycosides are oxidized by NaIO4 and reacted with a protein to give conjugates which are recognized with anti-solamargine monoclonal antibody (MAb. Anti-solamargine MAb having wide cross-reactivity can stain and detect all solasodine glycosides by fingerprint. Different sensitivity between solamargine and solasonine was observed. The detection limit was 1.6 ng of solasonine. The hydrolysed products of solamargine were determined by fingerprint of eastern blotting compared to their Rf values depending on the sugar number. Fingerprint by eastern blotting using anti-ginsenoside Rb1 MAb distinguished the formula containing ginseng prescribed in traditional Chinese medicine. By double-staining of ginsenosides it is possible to suggest that the staining color shows the pharmacological activity, such as the purple bands indicate ginsenosides having stimulation activity, and the blue color indicated compound like ginsenosides possessed the depression affect for the central nervous system (CNS, respectively.

  16. Cameroonian medicinal plants: Pharmacology and derived natural products

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    Thomas Efferth

    2010-10-01

    Full Text Available Many developing countries including Cameroon have mortality patterns that reflect high levels of infectious diseases and the risk of death during pregnancy and childbirth, in addition to cancers, cardiovascular diseases and chronic respiratory diseases that account for most deaths in the developed world. Several medicinal plants are used traditionally for their treatment. In this review, plants used in Cameroonian traditional medicine with evidence for the activities of their crude extracts and/or derived products have been discussed. A considerable number of plant extracts and isolated compounds possess significant antimicrobial, antiparasitic including anti-malarial, anti-proliferative, anti-inflammatory, anti-diabetes, and antioxidant effects. Most of the biologically active compounds belong to terpenoids, phenolics and alkaloids. Terpenoids from Cameroonian plants showed best activities as anti-parasitic, but rather poor antimicrobial effects. The best antimicrobial, anti-proliferative and antioxidant compounds were phenolics. In conclusion, many medicinal plants traditionally used in Cameroon to treat various ailments displayed good activities in vitro. This explains the endeavor of Cameroonian research institutes in drug discovery from indigenous medicinal plants. However, much work is still to be done to standardize methodologies and to study the mechanisms of action of isolated natural products.

  17. Toxic element contamination of natural health products and pharmaceutical preparations.

    Directory of Open Access Journals (Sweden)

    Stephen J Genuis

    Full Text Available BACKGROUND: Concern has recently emerged regarding the safety of natural health products (NHPs-therapies that are increasingly recommended by various health providers, including conventional physicians. Recognizing that most individuals in the Western world now consume vitamins and many take herbal agents, this study endeavored to determine levels of toxic element contamination within a range of NHPs. METHODS: Toxic element testing was performed on 121 NHPs (including Ayurvedic, traditional Chinese, and various marine-source products as well as 49 routinely prescribed pharmaceutical preparations. Testing was also performed on several batches of one prenatal supplement, with multiple samples tested within each batch. Results were compared to existing toxicant regulatory limits. RESULTS: Toxic element contamination was found in many supplements and pharmaceuticals; levels exceeding established limits were only found in a small percentage of the NHPs tested and none of the drugs tested. Some NHPs demonstrated contamination levels above preferred daily endpoints for mercury, cadmium, lead, arsenic or aluminum. NHPs manufactured in China generally had higher levels of mercury and aluminum. CONCLUSIONS: Exposure to toxic elements is occurring regularly as a result of some contaminated NHPs. Best practices for quality control-developed and implemented by the NHP industry with government oversight-is recommended to guard the safety of unsuspecting consumers.

  18. Recent progress in the development of synthetic hybrids of natural or unnatural bioactive compounds for medicinal chemistry.

    Science.gov (United States)

    Tsogoeva, Svetlana B

    2010-08-01

    The present mini-review highlights the recent developments on different classes of synthetic hybrids of natural and/or unnatural bioactive compounds, the utilization of which is very promising, as distinct features of each component can be hybridized and their properties leveraged. Particular stress is put on the respective mode of action and the corresponding rationale behind covalent combinations of various bioactive agents to increase their therapeutic potential, facilitate their administration, to reduce harmful side effects and/or to overcome the problem of multi-drug resistance. This rather recent approach has already found applications in the development of new anti-cancer, anti-Alzheimer, anti-malaria, anti-microbial therapeutics and other novel compounds with unprecedented bioactivity.

  19. Hemorrhagic stomatitis in a natural hybrid of Vipera ammodytes × Vipera berus due to inappropriate substrate in terrarium.

    Science.gov (United States)

    Czirják, Gábor Árpád; Köbölkuti, Lóránd Béla; Tenk, Miklós; Szakács, Attila; Kelemen, Attila; Spînu, Marina

    2015-06-01

    A natural hybrid of Vipera ammodytes × Vipera berus was presented having low body weight, seizures and generalized swelling of the cephalic region. Based on the history of the case and clinical examination, hemorrhagic stomatitis of traumatic origin was diagnosed. The snake was kept in a terrarium with wood chips as a substrate, and the material had induced trauma in the oral mucosa which was further complicated with Salmonella Arizonae and Morganella morganii co-infection, abscessation and osteomyelitis. To the best of the authors' knowledge, this is the first reported case of bacterial infection in European snake hybrids and one of a few case reports in European snakes. Although wood chips are an inexpensive substrate, based on our findings, they should be avoided when keeping and breeding European vipers.

  20. In vitro study of natural plant products against oral bacteria

    Institute of Scientific and Technical Information of China (English)

    Siddiqui R; Siti AsmaH; Tang L; Jie CC; Rosliza AR; Roziawati Y

    2009-01-01

    Objective:To analyze the effect of selected plant product against several bacterial which commonly causes oral infection.It was hope that in future,this product will become the remedy for treatment of oral infection and with the hope that it can substitute antibiotics.Methods:A total of 5 species of oral bacteria from American Type Culture Collection (ATCC)were employed in this study(S.mutans,S.aureus,P.aeruginosa,S.sobri-nus and L.salivarius).Three types of natural plants crude extracts were used (garlic,curry leaves and cloves).Bactericidal and bacteriostatic effects of these herbs were tested.Results:It was shown garlic had an-tibacterial effects on all bacteria.The Minimal Inhibitory Concentration (MIC in g/mL)of garlic towards S. aureus,P.aeruginosa,S.mutans,S.sobrinus and L.salivarius were 0.3,1.8,1.2,0.5 and 1.8,respectively. There was significant difference among the MIC of garlic on tested bacteria.It was more potent toward S.au-reus.The curry leaf solution on the other hand,did not show any zone of inhibition in all bacteria plates but adversely showed enhanced growth of those bacteria.Clove had shown its antibacterial effects on S.aureus and P.aeruginosa.The clove was more potent toward S.aureus with the MIC of 0.45 g/mL.P.aeruginosa was more sensitive to clove compared to garlic.For S.aureus,it was more sensitive to garlic compared to clove. Conclusion:The antibacterial activity of garlic and clove crude extracts shown in our study further confirm these natural plants'potential usage in therapeutic use for oral diseases or infections.This could be the platform for the interested party to do research and development on it and to produce oral health products which are more affordable for lower economic income groups and with fewer side effects as seen in synthetic drug.