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Sample records for sp lactucae electronic

  1. Volatiles emitted by Bacillus sp. BCT9 act as growth modulating agents on Lactuca sativa seedlings.

    Science.gov (United States)

    Fincheira, Paola; Parra, Leonardo; Mutis, Ana; Parada, Maribel; Quiroz, Andrés

    2017-10-01

    Chemical products are applied during horticulture to increase food production, but the environmental problems resulting from these applications have led to a search for more sustainable products. Volatile organic compounds (VOCs) demonstrating plant growth promoter (PGP) activity released by bacterial species have emerged as alternatives, but their effects on Lactuca sativa growth are unknown. In this study, VOCs released by Bacillus sp. BCT9 cultures grown in different media (Methyl Red & Voges Proskauer, Murashige & Skoog and nutrient media) at concentrations of 0.1, 0.2, 0.5 and 0.7 (measured as the absorbance, λ=600nm) were tested to evaluate their activity as growth inducers of L. sativa after 10days of exposure. Lower concentrations of BCT9 increased root length, and higher concentrations induced shoot length and lateral root length. The dry weight and number of lateral roots increased similarly, independent of concentration, for VOCs produced in all culture media. BCT9 cultures grown in Methyl Red & Voges Proskauer medium as bioactive compounds with or without lanolin. These VOCs increased shoot length, root length and dry weight at low concentrations, independent of the presence of lanolin. Lateral root length increased with the application of 2-nonanone (50ppm) and 2-undecanone (0.05ppm). Based on these results, the use of bioactive volatiles as growth inducers of horticultural species represents an alternative or complementary strategy. Copyright © 2017 Elsevier GmbH. All rights reserved.

  2. Rhizobacteria Pseudomonas fluorescens and Azospirillum sp. association enhances growth of Lactuca sativa L. under tropical conditions

    Directory of Open Access Journals (Sweden)

    Amael APONTE

    2017-06-01

    Full Text Available The selection of microorganisms that enhance plant growth and confer biotic and abiotic tolerance to crops constitutes a biotechnology currently gaining importance on a global scale. The aim of this investigation was to evaluate the effects of inoculating rhizobacteria to lettuce (Lactuca sativa L. on seed germination and vegetative development in order to use isolates as potential biofertilizers under tropical conditions. Five isolates of Pseudomonas fluorescens (Pf and one of Azospirillum sp. (Az were inoculated to seeds using a bacterial suspension of 1.5*108 CFU*mL-1. In vitro, none of the isolates promoted germination. In vivo, isolates promoted growth and acted as stress alleviators by conferring tolerance to high temperatures (≥ 30 °C. The highest seedling emergence percentages were induced by the association of P.fluorescens with Azospirillum. This association also promoted the highest leaf-area in 25 d seedlings and exhibited a significantly higher dry-weight in 40 d plants compared to the control (P≤0.05 supporting the advantages of bio-consortiums over individual strains. The strains were able to produce dependent L-tryptophan indole-3-acetic acid (IAA, to solubilize phosphorous in vitro and tolerated at least 5%-salt stress. The results indicate that isolate Pf (26 and Az possess plant growth promoting rhizobacteria (PGPR traits and should be further assessed. This study suggests that P. fluorescens and Azospirillum act synergically and are able to trigger an induced-tolerance mechanism in lettuce under abiotic stress.

  3. Effect of corn steep liquor on lettuce root rot (Fusarium oxysporum f.sp. lactucae) in hydroponic cultures.

    Science.gov (United States)

    Chinta, Yufita D; Kano, Kazuki; Widiastuti, Ani; Fukahori, Masaru; Kawasaki, Shizuka; Eguchi, Yumi; Misu, Hideyuki; Odani, Hiromitsu; Zhou, Songying; Narisawa, Kazuhiko; Fujiwara, Kazuki; Shinohara, Makoto; Sato, Tatsuo

    2014-08-01

    Recent reports indicate that organic fertilisers have a suppressive effect on the pathogens of plants grown under hydroponic systems. Furthermore, microorganisms exhibiting antagonistic activity to diseases have been observed in organic hydroponic systems. This study evaluated the effect of corn steep liquor (CSL) on controlling lettuce root rot disease [Fusarium oxysporum f.sp. lactucae (FOL)] in a hydroponic system. The effect of CSL and Otsuka A (a chemical fertiliser) on the inhibition of FOL in terms of mycelial growth inhibition was tested in vivo. Addition of CSL suppressed FOL infection rates. CSL inhibited FOL infection by 26.3-42.5% from 2 days after starting incubation. In comparison, Otsuka A inhibited FOL growth by 5.5-19.4%. In addition, four of 10 bacteria isolated from the nutrient media containing CSL exhibited inhibition zones preventing FOL mycelial growth. We found that CSL suppressed FOL in lettuce via its antifungal and biostimulatory effects. We suggest that activation of beneficial microorganisms present in CSL may be used to decrease lettuce root rot disease and contribute to lettuce root growth. © 2014 Society of Chemical Industry.

  4. The International Lactuca database

    NARCIS (Netherlands)

    Treuren, van R.; Menting, F.B.J.

    2014-01-01

    The International Lactuca Database includes accessions of species belonging to the genus Lactuca, but also a few accessions belonging to related genera. Passport data can be searched on-line or downloaded. Characterization and evaluation data can be accessed via the downloading section. Requests for

  5. Guaianolides from Lactuca saligna.

    Science.gov (United States)

    Khalil, A T; El-Fattah, H A; Mansour, E S

    1991-04-01

    The phytochemical investigation of the aerial parts of LACTUCA SALIGNA L. revealed the presence of lactucin, lactucopicrin, and a new guaianolide named 11beta,13-dihydrolactucopicrin. The structural configuration was established through spectral data.

  6. Lactuca sativa L.

    African Journals Online (AJOL)

    Jane

    2011-10-24

    Oct 24, 2011 ... Seeds of four lettuce (Lactuca sativa L.) genotypes viz., Great Lakes (GL), Paris Island cos, Kagraner. Sommer (KS) and Isadora were assessed for their response to salt at the germination and seedling stages. The germination rate of the four varieties was comparatively studied under 0, 50, 100, 150 and.

  7. ERRATUM Electron field emission from sp -induced insulating to ...

    Indian Academy of Sciences (India)

    Administrator

    Electron field emission from sp. 2. -induced insulating to metallic behaviour of amorphous carbon (a-C) films. Pitamber Mahanandia, P N Viswakarma, Prasad Vishnu Bhotla, S V Subramanyam and Karuna Kar Nanda. 2010 Bull. Mater. Sci. 33 pp 215–220. The MS received date should be read as “MS received 20 October ...

  8. Avaliação da contaminação por enteroparasitas em alfaces (lactuca sativa comercializadas em restaurantes com alimentos expostos ao consumo no município de Sorocaba/SP

    Directory of Open Access Journals (Sweden)

    Caio Vieira Magalhães Ornelas

    2015-10-01

    Full Text Available Diante de um cotidiano pauta do por uma intensa influência dos meios decomunicação a respeito da alimentação saudável e de baixo teor calórico,bem como de um progressivo número de campanhas sociais combatendoa obesidade e seu alto valor epidemiológico sobre a sociedadecontemporânea, as hortaliças têm recebido ampla ênfase no cenárionutricional dos dias de hoje. Entretanto, tais aspectos são tambémacompanhados de extrema cautela, uma vez que as hortaliças sãoimportantes veículos de infecções ao organismo humano através de umavasta gama de possíveis parasitas, devido à manipulação pré-consumo einclusive o consumo cru. O trabalho que se segue teve como objetivopesquisar a presença de enteroparasitas especificamente em alfacescomercializadas em restaurantes com alimentos expostos ao consumo nomunicípio de Sorocaba-SP. As amostras de alface crespa (Lactuca sativacoletadas foram submetidas a uma série de etapas para análise:inicialmente houve lavagem em sacos plásticos durante 30 minutos,seguida de sedimentação do líquido por 24 horas e, por fim, análiseparasitológica da amostra por microscopia óptica. Das 40 amostrasrealizadas, apenas 5% continham enteroparasitas. Outras duas amostrascontinham achados como Paramecium spp. e ácaro. Os resultadosreforçam a necessidade de um a boa higienização das hortaliças, mas,devido ao grande número de restaurantes em Sorocaba comparado com ode amostras coletadas, é inadequado considerar generalizar a premissade que os restaurantes self-service possuam alfaces crespa (Lactucasativa higienizadas e próprias para o consumo em Sorocaba.

  9. Origin and domestication of Lactuca sativa L.

    NARCIS (Netherlands)

    Vries, de I.M.

    1997-01-01

    The domestication of lettuce, Lactuca sativa L. is described on the basis of literature study. The centre of origin is discussed. A historical survey is made of the distribution of the groups of Lactuca cultivars over the world.

  10. Electron field emission from sp -induced insulating to metallic ...

    Indian Academy of Sciences (India)

    Administrator

    possible applications as semiconductor materials (Silva et al 1998) and as potential field emission cathode ... Though post treatment and annealing results in higher sp. 2 content cluster sizes, graphitization of the ... The samples were prepared by a simple pyrolysis method at different temperatures (700, 800 and 900°C) ...

  11. Electron field emission from sp 2-induced insulating to metallic ...

    Indian Academy of Sciences (India)

    The influence of concentration and size of 2 cluster on the transport properties and electron field emissions of amorphous carbon films have been investigated. The observed insulating to metallic behaviour from reduced activation energy derived from transport measurement and threshold field for electron emission of ...

  12. sp

    African Journals Online (AJOL)

    Vihar

    adopted as the first line drug. SP has few untoward effects if used carefully in therapeutic doses. Nausea, vomiting, generalized body weakness; diarrhea, skin rashes and hematological reactions are some of the associated side effects. The drug can cause severe skin reactions such as Steven Johnson's syndrome. This.

  13. Electron field emission from sp 2-induced insulating to metallic ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 33; Issue 3. Electron field emission from 2-induced insulating to metallic behaviour of amorphous carbon (-C) films. Pitamber Mahanandia P N Viswakarma Prasad Vishnu Bhotla S V Subramanyam Karuna Kar Nanda. Thin Films and Nanomatter Volume 33 Issue 3 ...

  14. Gifsla (Lactuca virosa L.) en kompassla (Lactuca serriola L.) in Nederland

    NARCIS (Netherlands)

    Ham, van der R.W.J.M.

    1981-01-01

    Induced by too many wrongly determined specimens of Lactuca virosa L. the author discusses a number of differences with Lactuca serriola L. The fruit especially offers reliable characters (fig. 3). L. virosa probably occurs only as an alien in the Netherlands. In recent years L. serriola had a

  15. A bioelectrochemical approach to characterize extracellular electron transfer by Synechocystis sp. PCC6803.

    Directory of Open Access Journals (Sweden)

    Angelo Cereda

    Full Text Available Biophotovoltaic devices employ photosynthetic organisms at the anode of a microbial fuel cell to generate electrical power. Although a range of cyanobacteria and algae have been shown to generate photocurrent in devices of a multitude of architectures, mechanistic understanding of extracellular electron transfer by phototrophs remains minimal. Here we describe a mediatorless bioelectrochemical device to measure the electrogenic output of a planktonically grown cyanobacterium, Synechocystis sp. PCC6803. Light dependent production of current is measured, and its magnitude is shown to scale with microbial cell concentration and light intensity. Bioelectrochemical characterization of a Synechocystis mutant lacking Photosystem II demonstrates conclusively that production of the majority of photocurrent requires a functional water splitting aparatus and electrons are likely ultimately derived from water. This shows the potential of the device to rapidly and quantitatively characterize photocurrent production by genetically modified strains, an approach that can be used in future studies to delineate the mechanisms of cyanobacterial extracellular electron transport.

  16. Energy production from marine biomass (Ulva lactuca)

    Energy Technology Data Exchange (ETDEWEB)

    Nikolaisen, L.; Daugbjerg Jensen, P.; Svane Bech, K. [Danish Technological Institute (DTI), Taastrup (Denmark)] [and others

    2011-11-15

    In this project, methods for producing liquid, gaseous and solid biofuel from the marine macroalgae Ulva lactuca has been studied. To get an understanding of the growth conditions of Ulva lactuca, laboratory scale growth experiments describing N, P, and CO{sub 2} uptake and possible N{sub 2}O and CH{sub 4} production are carried out. The macroalgae have been converted to bioethanol and methane (biogas) in laboratory processes. Further the potential of using the algae as a solid combustible biofuel is studied. Harvest and conditioning procedures are described together with the potential of integrating macroalgae production at a power plant. The overall conclusions are: 1. Annual yield of Ulva lactuca is 4-5 times land-based energy crops. 2. Potential for increased growth rate when bubbling with flue gas is up to 20%. 3. Ethanol/butanol can be produced from pretreated Ulva of C6 and - for butanol - also C5 sugars. Fermentation inhibitors can possibly be removed by mechanical pressing. The ethanol production is 0,14 gram pr gram dry Ulva lactuca. The butanol production is lower. 4. Methane yields of Ulva are at a level between cow manure and energy crops. 5. Fast pyrolysis produces algae oil which contains 78 % of the energy content of the biomass. 6. Catalytic supercritical water gasification of Ulva lactuca is feasible and a methane rich gas can be obtained. 7. Thermal conversion of Ulva is possible with special equipment as low temperature gasification and grate firing. 8. Co-firing of Ulva with coal in power plants is limited due to high ash content. 9. Production of Ulva only for energy purposes at power plants is too costly. 10. N{sub 2}O emission has been observed in lab scale, but not in pilot scale production. 11. Analyses of ash from Ulva lactuca indicates it as a source for high value fertilizers. 12. Co-digestion of Ulva lactuca together with cattle manure did not alter the overall fertilization value of the digested cattle manure alone. (LN)

  17. Removal of cadmium from aqueous solution using marine green algae, Ulva lactuca

    Directory of Open Access Journals (Sweden)

    Mohamed M. Ghoneim

    2014-01-01

    Full Text Available The present study aimed to evaluate the efficiency of marine algae for removal of metals from the aqueous solution. The green alga, Ulva lactuca, collected from the intertidal zone of the Suez Bay, northern part of the Red Sea was used to reduce cadmium levels from the aqueous solutions. The biosorption mechanisms of Cd2+ ions onto the algal tissues were examined using various analytical techniques: Fourier-transform infrared spectroscopy (FT-IR and Scanning electron microscopy (SEM. Results indicated that at the optimum pH value of 5.5; about 0.1 g of U. lactuca was enough to remove 99.2% of 10 mg L−1 Cd2+ at 30 °C in the aqueous solutions. The equilibrium data were well fitted with the Langmuir and Freundlich isotherms. The monolayer adsorption capacity was 29.1 mg g−1. The calculated RL and ‘n’ values have proved the favorability of cadmium adsorption onto U. lactuca. The desorption test revealed that HCl was the best for the elution of metals from the tested alga. In conclusion, the seaweed U. lactuca was the favorable alternative of cadmium removal from water.

  18. Effect of exogenous electron shuttles on growth and fermentative metabolism in Clostridium sp. BC1

    Energy Technology Data Exchange (ETDEWEB)

    Yarlagadda V. N.; Francis A.; Gupta, A.; Dodge, C. J.

    2012-03-01

    In this study, the influence exogenous electron shuttles on the growth and glucose fermentative metabolism of Clostridium sp. BC1 was investigated. Bicarbonate addition to mineral salts (MS) medium accelerated growth and glucose fermentation which shifted acidogenesis (acetic- and butyric-acids) towards solventogenesis (ethanol and butanol). Addition of ferrihydrite, anthraquinone disulfonate, and nicotinamide adenine dinucleotide in bicarbonate to growing culture showed no significant influence on fermentative metabolism. In contrast, methyl viologen (MV) enhanced ethanol- and butanol-production by 28- and 12-fold, respectively with concomitant decrease in hydrogen, acetic- and butyric-acids compared to MS medium. The results show that MV addition affects hydrogenase activity with a significant reduction in hydrogen production and a shift in the direction of electron flow towards enhanced production of ethanol and butanol.

  19. Complete genome sequence of the biofilm-formingCurtobacteriumsp. strain BH-2-1-1, isolated from lettuce (Lactuca sativa) originating from a conventional field in Norway.

    Science.gov (United States)

    Dees, Merete Wiken; Brurberg, May Bente; Lysøe, Erik

    2016-12-01

    Here, we present the 3,795,952 bp complete genome sequence of the biofilm-forming Curtobacterium sp. strain BH-2-1-1, isolated from conventionally grown lettuce ( Lactuca sativa ) from a field in Vestfold, Norway. The nucleotide sequence of this genome was deposited into NCBI GenBank under the accession CP017580.

  20. Acinetobacter lactucae sp. nov., isolated from iceberg lettuce (Asteraceae: Lactuca sativa)

    Science.gov (United States)

    Strain NRRL B-41902 and three closely related strains were isolated from iceberg lettuce. The strain was found to consist of strictly aerobic, gram-negative rods that formed cocci in late stationary phase. Subsequent to sequencing the 16S ribosomal RNA gene, it was found that strain NRRL B-41902 was...

  1. Genetic diversity and evolution in Lactuca L. (Asteraceae)

    NARCIS (Netherlands)

    Wei, Z.

    2016-01-01

    Cultivated lettuce (Lactuca sativa L.) is an important leafy vegetable worldwide. However, the phylogenetic relationships between domesticated lettuce and its wild relatives are still not clear. In this thesis, I focus on the phylogenetic relationships within Lactuca L., including an analysis of the

  2. Genetic diversity and evolution in Lactuca L. (Asteraceae)

    NARCIS (Netherlands)

    Wei, Z.

    2016-01-01

    Cultivated lettuce (Lactuca sativa L.) is an important leafy vegetable worldwide. However, the phylogenetic relationships between domesticated lettuce and its wild relatives are still not clear. In this thesis, I focus on the phylogenetic relationships within Lactuca L.,

  3. Nutritional value of green seaweed (Ulva lactuca for broiler chickens

    Directory of Open Access Journals (Sweden)

    Alaeldein M. Abudabos

    2013-04-01

    Full Text Available The current work aimed to assess the potential of the green seaweed Ulva lactuca (U. lactuca as an alternative ingredient in broiler chicken diets. The effect of substituting 1.0 or 3.0% of corn with U. lactuca on performance, carcass characteristics, serum constituents and nutrients retention of broilers from 12 to 33 d of age was evaluated. Three treatments were distributed in a RCBD design: T1 = control diet (0% U. lactuca; T2 = 1.0 % U. lactuca; T3 = 3.0 % U. lactuca. Cumulative feed intake (FI, body weight gain (BWG, feed conversion ratio (FCR and nutrients retention from 12 to 33 d of age were not affected by treatment (P>0.05. Birds which had received T3 had a higher dressing percentage and breast muscle yield compared to those which had received T1 or T2. Serum total lipid, cholesterol and uric acid concentrations were significantly lower in birds which had received T2 and T3 (P<0.05. Serum enzymes and electrolytes were not influenced by any dietary treatment except for alanine transaminase (ALT which was significantly lower for the treated groups. Based on presented evidences, it is recommended to substitute 3.0% of corn with green seaweed (U. lactuca.

  4. Local coordination, electronic correlations and relation between thermodynamic and transport properties of sp liquid metals

    Science.gov (United States)

    March, N. H.

    A brief discussion on local coordination in expanded alkalis will be followed by a short review of recent progress in determining electronic correlation functions by combining experiment using diffraction techniques with computer simulation. Then both critical point properties and melting temperatures of liquid sp metals will be discussed. In the latter case, the main topic will be on a metal model which will be used to correlate the ratio of surface tension to shear viscosity with a characteristic velocity. Conventional choice is to take this velocity as the thermal value (kBT / M)1/2. This choice has some merit. However an alternative is to use the velocity of sound, and a different formula then emerges which depends on the valency Z. Reference to some experimental support for such a formula is given. Finally, connection with diffusion, and with bulk viscosity, is discussed with some involvement of a collective mode model, such as prompted by early neutron inelastic scattering results on Rb near its melting point.

  5. Light and electron microscope observations on Nephroselmis gaoae sp. nov. (Prasinophyceae)

    Science.gov (United States)

    Tseng, C. K.; Jiao-Fen, Chen; Zhe-Fu, Zhang; Hui-Qi, Zhang

    1994-09-01

    Nephroselmis gaoae sp. nov. is described on the basis of light and electron microscope observations of cultured material originally collected and isolated from seawater of Jiaozhou Bay, Qingdao, China. The periplasts on the cell body and flagella are covered by five types of scales, two types on the flagella and three on the body. Among these, the morphology and the number of spines of large stellate body scales differ remarkably from those of previously described species of Nephroselmis. Apart from these, the unusual fine structure of the eyespot (stigma) is very characteristic. As in the other species of Nephroselmis, the eyespot lies immediately under the two-membraned chloroplast envelope; unlike the others, however, it is not composed of a number of osmiophilic globules, but consists of about 14 curved rod-shaped osmiophilic bodies arranged loosely and randomly. This feature distinguishes the present new species not only from the other species of Nephroselmis but also from the other motile algal species, the eyespots structure of which had been previously described.

  6. Electronic detection of Drechslera sp. fungi in charentais melon ( Cucumis melo Naudin) using carbon-nanostructure-based sensors.

    Science.gov (United States)

    Greenshields, Márcia W C C; Mamo, Messai A; Coville, Neil J; Spina, Andréa P; Rosso, Diogo Filipe; Latocheski, Elaine C; Destro, João Guilherme; Pimentel, Ida C; Hümmelgen, Ivo A

    2012-10-24

    The development of chemical sensor technology in recent years has stimulated an interest regarding the use of characteristic volatiles and odors as a rapid and early indication of deterioration in fruit quality. The fungal infestation by Drechslera sp. in melons is a severe problem, and we demonstrate that electronic sensors based on carbon nanostructures are able to detect the presence of these fungi in melon. The responses of sensor conductance G and capacitance C at 27 kHz were measured and used to calculate their ΔG and ΔC variation over the full melon ripening process under shelf conditions with proliferation of Drechslera sp. fungi. The sensor response showed that these fungi can be electronically identified in charentais melon, constituting an effective and cheap test procedure to differentiate between infected and uninfected melon.

  7. Complete genome sequence of the biofilm-formingMicrobacteriumsp. strain BH-3-3-3, isolated from conventional field-grown lettuce (Lactuca sativa) in Norway.

    Science.gov (United States)

    Dees, Merete Wiken; Brurberg, May Bente; Lysøe, Erik

    2017-03-01

    The genus Microbacterium contains bacteria that are ubiquitously distributed in various environments and includes plant-associated bacteria that are able to colonize tissue of agricultural crop plants. Here, we report the 3,508,491 bp complete genome sequence of Microbacterium sp. strain BH-3-3-3, isolated from conventionally grown lettuce ( Lactuca sativa ) from a field in Vestfold, Norway. The nucleotide sequence of this genome was deposited into NCBI GenBank under the accession CP017674.

  8. Analgesic and anti-inflammatory actions on bradykinin route of a polysulfated fraction from alga Ulva lactuca.

    Science.gov (United States)

    de Araújo, Ianna Wivianne Fernandes; Rodrigues, José Ariévilo Gurgel; Quinderé, Ana Luíza Gomes; Silva, Jane de Fátima Teixeira; Maciel, Gabrielle de Freitas; Ribeiro, Natássia Albuquerque; de Sousa Oliveira Vanderlei, Edfranck; Ribeiro, Kátia Alves; Chaves, Hellíada Vasconcelos; Pereira, Karuza Maria Alves; Bezerra, Mirna Marques; Benevides, Norma Maria Barros

    2016-11-01

    We investigated structural features of polysaccharides from Ulva lactuca and their effects on the classical models of nociception and inflammation. Crude extract was obtained by enzymatic digestion and isolated by ion exchange chromatography on DEAE-cellulose. The fraction with higher yield was used in the tests (SP-Ul). Swiss mice received SP-Ul (1, 3 or 9mg/kg; i.v.), 30min prior to injection of 0.8%-acetic acid or 1%-formalin or prior to a thermal stimulus. At same doses, SP-Ul was tested on Wistar rats on paw edema elicited by different irritants (carrageenan, dextran, bradykinin, histamine or serotonin). The results of infrared characterization indicated the presence of hydroxyl groups, sulfate, uronic acid and glycosidic linkages in all SP fractions spectrums. SP-Ul decreased significantly the antinociception in response to acetic acid or formalin (second phase), but not in the hot-plate test, suggesting that its analgesia occurs through a peripheral mechanism. SP-Ul did not reduce carrageenan-induced paw edema as supported by both histological and myeloperoxidase activity assessments. However, SP-Ul (1mg/kg; s.c.) reduced dextran-elicited edema, showing vascular anti-inflammatory effect, with bradykinin as major target because it did not reduce histamine- and serotonin-induced paw edemas. Therefore, SP-Ul acts on bradykinin pathway in its antinociceptive and anti-inflammatory responses. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Extracellular Electron Transfer Mediated by Flavins in Gram-positive Bacillus sp. WS-XY1 and Yeast Pichia stipitis

    International Nuclear Information System (INIS)

    Wu, Song; Xiao, Yong; Wang, Lu; Zheng, Yue; Chang, Kenlin; Zheng, Zhiyong; Yang, Zhaohui; Varcoe, John R.; Zhao, Feng

    2014-01-01

    Extracellular electron transfer (EET) of microorganisms represents a communicative bridge between the interior and exterior of the cells. Most prior EET studies have focused on Gram-negative bacteria. However, fungi and Gram-positive bacteria, that contain dense cellular walls, have rarely been reported. Herein, two model dense cell wall microorganisms (Bacillus sp. WS-XY1 and the yeast Pichia stipitis) were identified to be electrochemically active. Further analysis indicated that the two microorganisms were able to secrete flavins to mediate their EET. The discovery, that dense cell wall containing microorganisms can undertake mediated EET, adds to the body of knowledge towards building a comprehensive understanding of biogeochemical and bioelectrical processes

  10. Effect of metal sulfide pulp density on gene expression of electron transporters in Acidithiobacillus sp. FJ2.

    Science.gov (United States)

    Fatemi, Faezeh; Miri, Saba; Jahani, Samaneh

    2017-05-01

    In Acidithiobacillus ferrooxidans, one of the most important bioleaching bacterial species, the proteins encoded by the rus operon are involved in the electron transfer from Fe 2+ to O 2 . To obtain further knowledge about the mechanism(s) involved in the adaptive responses of the bacteria to growth on the different uranium ore pulp densities, we analyzed the expression of the four genes from the rus operon by real-time PCR, when Acidithiobacillus sp. FJ2 was grown in the presence of different uranium concentrations. The uranium bioleaching results showed the inhibitory effects of the metal pulp densities on the oxidation activity of the bacteria which can affect Eh, pH, Fe oxidation and uranium extractions. Gene expression analysis indicated that Acidithiobacillus sp. FJ2 tries to survive in the stress with increasing in the expression levels of cyc2, cyc1, rus and coxB, but the metal toxicity has a negative effect on the gene expression in different pulp densities. These results indicated that Acidithiobacillus sp. FJ2 could leach the uranium even in high pulp density (50%) by modulation in rus operon gene responses.

  11. A dosimetric survey of the DC1500/25/04 electron beam plant installed at IPEN-CNEN/SP

    International Nuclear Information System (INIS)

    Kuntz, Florent; Somessari, Elizabeth S.R.; Silveira, Carlos G.da; Bueno, Carmen C.; Calvo, Wilson A.P.; Napolitano, Celia M.; Goncalves, Josemary A.C.; Somessari, Samir L.

    2015-01-01

    In this work we describe a dosimetric survey of the DC1500/25/04 electron beam accelerator installed in the Intense Sources of Radiation Laboratory at IPEN/CNEN-SP. As this accelerator has been used for innumerable applications in radiation processing, product surface and internal doses must be targeted and controlled via operational qualification such as beam energy, beam current, scan width and conveyor speed. The qualification of the accelerator was carried out in order to observe the current performances of the irradiation plant using Alanine (ESR) and CTA (UV Spectrophotometry) dosimeters. Energy (Electron penetration in material) calculations, scanning width/length, homogeneity and irradiation uniformity were evaluated according to ISO/ASTM 51649 and ISO11137-3, as well as process uncertainty establishment. (author)

  12. Influence of Carbon Sources and Electron Shuttles on Ferric Iron Reduction by Cellulomonas sp. Strain ES6

    Energy Technology Data Exchange (ETDEWEB)

    Dr Robin Gerlach; Erin K. Field; Sridhar Viamajala; Brent M. Peyton; William A. Apel; Al B. Cunningham

    2011-09-01

    Microbially reduced iron minerals can reductively transform a variety of contaminants including heavy metals, radionuclides, chlorinated aliphatics, and nitroaromatics. A number of Cellulomonas spp. strains, including strain ES6, isolated from aquifer samples obtained at the U.S. Department of Energy's Hanford site in Washington, have been shown to be capable of reducing Cr(VI), TNT, natural organic matter, and soluble ferric iron [Fe(III)]. This research investigated the ability of Cellulomonas sp. strain ES6 to reduce solid phase and dissolved Fe(III) utilizing different carbon sources and various electron shuttling compounds. Results suggest that Fe(III) reduction by and growth of strain ES6 was dependent upon the type of electron donor, the form of iron present, and the presence of synthetic or natural organic matter, such as anthraquinone-2,6-disulfonate (AQDS) or humic substances. This research suggests that Cellulomonas sp. strain ES6 could play a significant role in metal reduction in the Hanford subsurface and that the choice of carbon source and organic matter addition can allow for independent control of growth and iron reduction activity.

  13. Influence of carbon sources and electron shuttles on ferric iron reduction by Cellulomonas sp. strain ES6.

    Science.gov (United States)

    Gerlach, Robin; Field, Erin K; Viamajala, Sridhar; Peyton, Brent M; Apel, William A; Cunningham, Al B

    2011-09-01

    Microbially reduced iron minerals can reductively transform a variety of contaminants including heavy metals, radionuclides, chlorinated aliphatics, and nitroaromatics. A number of Cellulomonas spp. strains, including strain ES6, isolated from aquifer samples obtained at the U.S. Department of Energy's Hanford site in Washington, have been shown to be capable of reducing Cr(VI), TNT, natural organic matter, and soluble ferric iron [Fe(III)]. This research investigated the ability of Cellulomonas sp. strain ES6 to reduce solid phase and dissolved Fe(III) utilizing different carbon sources and various electron shuttling compounds. Results suggest that Fe(III) reduction by and growth of strain ES6 was dependent upon the type of electron donor, the form of iron present, and the presence of synthetic or natural organic matter, such as anthraquinone-2,6-disulfonate (AQDS) or humic substances. This research suggests that Cellulomonas sp. strain ES6 could play a significant role in metal reduction in the Hanford subsurface and that the choice of carbon source and organic matter addition can allow for independent control of growth and iron reduction activity.

  14. Characterization of the sp sup 2 bonds network in a-C:H layers with nuclear magnetic resonance, electron energy loss spectroscopy and electron spin resonance

    Energy Technology Data Exchange (ETDEWEB)

    Kleber, R.; Jung, K.; Ehrhardt, H. (Fachbereich Physik, Univ. Kaiserslautern (Germany)); Muehling, I.; Breuer, K. (Technische Univ. Chemnitz, Sektion Physik/Elektronische Bauelemente (Germany)); Metz, H.; Engelke, F. (Karl-Marx-Univ., Sektion Physik, Leipzig (Germany))

    1991-12-01

    a-C:H layers prepared at different ion energies have been investigated by several methods including {sup 13}C nuclear magnetic resonance (NMR), electron energy loss spectroscopy (EELS) and electron spin resonance (ESR). The sp{sup 2} fraction of the samples rose from 27% to about 60 at.% with increasing ion energies from 30 eV to 170 eV. In the EELS spectra of these layers the intensity of the {pi}{yields}{pi}{sup *} transition between 4 and 7 eV showed no significant variation. But a shift of the peak is observed from 7 eV to lower energy losses with increasing ion energies indicating an enhanced formation of larger sp{sup 2} cluster sizes. This shift is accompanied by a broadening of the energy loss peak, suggesting a broadening of the cluster size distribution. The ESR spectra showed an increase of the spin density by more than one order of magnitude with increasing ion energies. Simultaneously the linewidth of the ESR signal gets narrower. This can also be interpreted as an increasing cluster size from single benzene rings to three and four fused six-fold rings. Hence, the EELS and ESR spectra lead to the same conclusions with respect to the microstructure of the a-C:H network. (orig.).

  15. FLAVODIIRON2 and FLAVODIIRON4 Proteins Mediate an Oxygen-Dependent Alternative Electron Flow in Synechocystis sp. PCC 6803 under CO2-Limited Conditions1[OPEN

    Science.gov (United States)

    Shimakawa, Ginga; Shaku, Keiichiro; Nishi, Akiko; Hayashi, Ryosuke; Yamamoto, Hiroshi; Sakamoto, Katsuhiko; Makino, Amane; Miyake, Chikahiro

    2015-01-01

    This study aims to elucidate the molecular mechanism of an alternative electron flow (AEF) functioning under suppressed (CO2-limited) photosynthesis in the cyanobacterium Synechocystis sp. PCC 6803. Photosynthetic linear electron flow, evaluated as the quantum yield of photosystem II [Y(II)], reaches a maximum shortly after the onset of actinic illumination. Thereafter, Y(II) transiently decreases concomitantly with a decrease in the photosynthetic oxygen evolution rate and then recovers to a rate that is close to the initial maximum. These results show that CO2 limitation suppresses photosynthesis and induces AEF. In contrast to the wild type, Synechocystis sp. PCC 6803 mutants deficient in the genes encoding FLAVODIIRON2 (FLV2) and FLV4 proteins show no recovery of Y(II) after prolonged illumination. However, Synechocystis sp. PCC 6803 mutants deficient in genes encoding proteins functioning in photorespiration show AEF activity similar to the wild type. In contrast to Synechocystis sp. PCC 6803, the cyanobacterium Synechococcus elongatus PCC 7942 has no FLV proteins with high homology to FLV2 and FLV4 in Synechocystis sp. PCC 6803. This lack of FLV2/4 may explain why AEF is not induced under CO2-limited photosynthesis in S. elongatus PCC 7942. As the glutathione S-transferase fusion protein overexpressed in Escherichia coli exhibits NADH-dependent oxygen reduction to water, we suggest that FLV2 and FLV4 mediate oxygen-dependent AEF in Synechocystis sp. PCC 6803 when electron acceptors such as CO2 are not available. PMID:25540330

  16. Occupational contact dermatitis from Cichorium (chicory, endive) and Lactuca (lettuce).

    Science.gov (United States)

    Friis, B; Hjorth, N; Vail, J T; Mitchell, J C

    1975-10-01

    In two cases, occupational contact dermatitis was found to be due to chicory (Cichorium) used as a salad plant. In one of the two cases, contact sensitivity to letuce (Lactuca) was also observed. The sesquiterpene lactones of the plant may be the allergens.

  17. Lactuca serriola (Asteraceae, a Newly Naturalized Plant in Taiwan

    Directory of Open Access Journals (Sweden)

    Chiu-Mei Wang

    2010-09-01

    Full Text Available A newly naturalized herb was recently recorded here. Lactuca serriola L. (Asteraceae was found in the central part of western Taiwan and Penghu island, as an alien weed. This report gives taxonomic descriptions and illustrations. Photographs are also provided for identification.

  18. Genetic transformation of lettuce (Lactuca sativa): A review

    African Journals Online (AJOL)

    SAM

    2014-04-16

    Apr 16, 2014 ... Lettuce (Lactuca sativa L.) is a globally important leafy vegetable that can be grown worldwide. Due to the rapid growth of population and the human desire to progress, there have been a lot of studies made by researchers, especially in genetic engineering. Improvements in regeneration system and.

  19. Genetic transformation of lettuce ( Lactuca sativa ): A review | Dan ...

    African Journals Online (AJOL)

    Lettuce (Lactuca sativa L.) is a globally important leafy vegetable that can be grown worldwide. Due to the rapid growth of population and the human desire to progress, there have been a lot of studies made by researchers, especially in genetic engineering. Improvements in regeneration system and transformation ...

  20. Effects of selected electron transport chain inhibitors on 24-h hydrogen production by Synechocystis sp. PCC 6803.

    Science.gov (United States)

    Burrows, Elizabeth H; Chaplen, Frank W R; Ely, Roger L

    2011-02-01

    One factor limiting biosolar hydrogen (H(2)) production from cyanobacteria is electron availability to the hydrogenase enzyme. In order to optimize 24-h H(2) production this study used Response Surface Methodology and Q2, an optimization algorithm, to investigate the effects of five inhibitors of the photosynthetic and respiratory electron transport chains of Synechocystis sp. PCC 6803. Over 3 days of diurnal light/dark cycling, with the optimized combination of 9.4 mM KCN (3.1 μmol 10(10) cells(-1)) and 1.5 mM malonate (0.5 μmol 10(10) cells(-1)) the H(2) production was 30-fold higher, in EHB-1 media previously optimized for nitrogen (N), sulfur (S), and carbon (C) concentrations (Burrows et al., 2008). In addition, glycogen concentration was measured over 24 h with two light/dark cycling regimes in both standard BG-11 and EHB-1 media. The results suggest that electron flow as well as glycogen accumulation should be optimized in systems engineered for maximal H(2) output. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Changes in Microtubular Alignment in Lactuca spp. (Asteraceae) Epidermal Cells during Early Stages of Infection by Bremia lactucae (Peronosporaceae)

    Czech Academy of Sciences Publication Activity Database

    Sedlářová, M.; Binarová, Pavla; Lebeda, A.

    2001-01-01

    Roč. 41, č. 1 (2001), s. 21-34 ISSN 0079-2047 R&D Projects: GA AV ČR IAA5020803; GA MŠk ME 397 Institutional research plan: CEZ:AV0Z5038910 Keywords : Bremia lactucae * Peronosporaceae * resistance Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.275, year: 2001

  2. Influence of Carbon Sources and Electron Shuttles on Ferric Iron Reduction by Cellulomonas sp. Strain ES6

    Energy Technology Data Exchange (ETDEWEB)

    Erin K. Field; Robin Gerlach; Sridhar Viamajala; Laura K. Jennings; Alfred B. Cunningham; Brent M. Peyton; William A. Apel

    2011-09-01

    The reduction of hexavalent chromium, Cr(VI), to trivalent chromium, Cr(III), can be an important aspect of remediation processes at Department of Energy (DOE) and other contaminated sites. Cellulomonas species are found at several Cr(VI) contaminated and uncontaminated locations at the DOE site in Hanford, Washington. Members of this genus have demonstrated the ability to effectively reduce Cr(VI) to Cr(III) fermentatively and therefore play a potential role in hexavalent chromium remediation at this site. Batch studies were conducted with Cellulomonas sp. strain ES6 to assess the influence of various carbon sources, iron minerals, and electron shuttling compounds on Cr(VI) reduction. These chemical species are likely to be present in these terrestrial environments during in situ bioremediation. Results indicated that there were a number of interactions between these compounds that influenced Cr(VI) reduction rates. The type of carbon source as well as the type of electron shuttle present influenced Cr(VI) reduction rates. When an electron shuttle, such as anthraquinone-2,6-disulfonate (AQDS), was present in the system, reduction rates increased significantly. Biologically reduced AQDS (AHDS) reduced Cr(VI) almost instantaneously. The presence of iron minerals and their concentrations did not significantly influence Cr(VI) reduction rates. However, strain ES6 or AQDS could directly reduce surface-associated Fe(III) to Fe(II) which was capable of reducing Cr(VI) at a near instantaneous rate. These results suggest the rate limiting step in these systems is the transfer of electrons from strain ES6 to the intermediate or terminal electron acceptor whether that is Cr(VI), Fe(III), or AQDS.

  3. Hexavalent chromium reduction by Cellulomonas sp. strain ES6: the influence of carbon source, iron minerals, and electron shuttling compounds.

    Science.gov (United States)

    Field, Erin K; Gerlach, Robin; Viamajala, Sridhar; Jennings, Laura K; Peyton, Brent M; Apel, William A

    2013-06-01

    The reduction of hexavalent chromium, Cr(VI), to trivalent chromium, Cr(III), can be an important aspect of remediation processes at contaminated sites. Cellulomonas species are found at several Cr(VI) contaminated and uncontaminated locations at the Department of Energy site in Hanford, Washington. Members of this genus have demonstrated the ability to effectively reduce Cr(VI) to Cr(III) fermentatively and therefore play a potential role in Cr(VI) remediation at this site. Batch studies were conducted with Cellulomonas sp. strain ES6 to assess the influence of various carbon sources, iron minerals, and electron shuttling compounds on Cr(VI) reduction rates as these chemical species are likely to be present in, or added to, the environment during in situ bioremediation. Results indicated that the type of carbon source as well as the type of electron shuttle present influenced Cr(VI) reduction rates. Molasses stimulated Cr(VI) reduction more effectively than pure sucrose, presumably due to presence of more easily utilizable sugars, electron shuttling compounds or compounds with direct Cr(VI) reduction capabilities. Cr(VI) reduction rates increased with increasing concentration of anthraquinone-2,6-disulfonate (AQDS) regardless of the carbon source. The presence of iron minerals and their concentrations did not significantly influence Cr(VI) reduction rates. However, strain ES6 or AQDS could directly reduce surface-associated Fe(III) to Fe(II), which was capable of reducing Cr(VI) at a near instantaneous rate. These results suggest the rate limiting step in these systems was the transfer of electrons from strain ES6 to the intermediate or terminal electron acceptor whether that was Cr(VI), Fe(III), or AQDS.

  4. Open reading frame ssr2016 is required for antimycin A-sensitive photosystem I-driven cyclic electron flow in the cyanobacterium Synechocystis sp. PCC 6803

    NARCIS (Netherlands)

    Yeremenko, Nataliya; Jeanjean, Robert; Prommeenate, Peerada; Krasikov, Vladimir; Nixon, Peter J.; Vermaas, Wim F. J.; Havaux, Michel; Matthijs, Hans C. P.

    2005-01-01

    Open reading frame ssr2016 encodes a protein with substantial sequence similarities to PGR5 identified as a component of the antimycin A-sensitive ferredoxin:plastoquinone reductase (FQR) in PSI cyclic photophosphorylation in Arabidopsis thaliana. We studied cyclic electron flow in Synechocystis sp.

  5. Ionizing radiation from 60Co and electron accelerator in reducing the population of Salmonella sp. inoculated in chicken meatballs: evaluation of acceptance by consumer

    International Nuclear Information System (INIS)

    Saito, Juliana

    2003-01-01

    Salmonella sp. is one of the main microorganisms that causes outbreaks of food borne diseases associated to poultry, and among its derivatives, the chicken meatballs are getting the favorites of the consumer. In the attempt to improve microbiological food safety, a method that has been hardly studied is the irradiation. To study the viability of the use o ionizing radiation originated from 60 Co and electrons accelerator in the reduction of Salmonella sp., frozen chickens meatballs were inoculated with 10 4 CFU/g of Salmonella sp., with needle and syringe. Subsequently they were exposure to doses of 1.5, 2.0, 2.5 and 3.0 kGy and Salmonella sp. was enumerated. Chicken meatballs were exposed to doses 3.0, 4.0 and 5.0 kGy and submitted to sensory analysis. The gamma radiation from 60 CO was effective in the reduction of Salmonella sp. inoculated in chicken meatballs. The ionizing radiation originated from electron beam was not effective in the conditions applied in this research. The commercial chicken meatballs prepared with chicken meat, mixed up with soy protein, seasoning and anti-oxidants additives did not loose their sensorial quality when exposure to doses of 3.0, 4.0 and 5.0 kGy and, in a general way, the consumers showed to be disposed to buy the irradiation product (author)

  6. FLAVODIIRON2 and FLAVODIIRON4 proteins mediate an oxygen-dependent alternative electron flow in Synechocystis sp. PCC 6803 under CO2-limited conditions.

    Science.gov (United States)

    Shimakawa, Ginga; Shaku, Keiichiro; Nishi, Akiko; Hayashi, Ryosuke; Yamamoto, Hiroshi; Sakamoto, Katsuhiko; Makino, Amane; Miyake, Chikahiro

    2015-02-01

    This study aims to elucidate the molecular mechanism of an alternative electron flow (AEF) functioning under suppressed (CO2-limited) photosynthesis in the cyanobacterium Synechocystis sp. PCC 6803. Photosynthetic linear electron flow, evaluated as the quantum yield of photosystem II [Y(II)], reaches a maximum shortly after the onset of actinic illumination. Thereafter, Y(II) transiently decreases concomitantly with a decrease in the photosynthetic oxygen evolution rate and then recovers to a rate that is close to the initial maximum. These results show that CO2 limitation suppresses photosynthesis and induces AEF. In contrast to the wild type, Synechocystis sp. PCC 6803 mutants deficient in the genes encoding FLAVODIIRON2 (FLV2) and FLV4 proteins show no recovery of Y(II) after prolonged illumination. However, Synechocystis sp. PCC 6803 mutants deficient in genes encoding proteins functioning in photorespiration show AEF activity similar to the wild type. In contrast to Synechocystis sp. PCC 6803, the cyanobacterium Synechococcus elongatus PCC 7942 has no FLV proteins with high homology to FLV2 and FLV4 in Synechocystis sp. PCC 6803. This lack of FLV2/4 may explain why AEF is not induced under CO2-limited photosynthesis in S. elongatus PCC 7942. As the glutathione S-transferase fusion protein overexpressed in Escherichia coli exhibits NADH-dependent oxygen reduction to water, we suggest that FLV2 and FLV4 mediate oxygen-dependent AEF in Synechocystis sp. PCC 6803 when electron acceptors such as CO2 are not available. © 2015 American Society of Plant Biologists. All Rights Reserved.

  7. Cadmium effects on growth and physiology of Ulva lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Markham, J.W.; Kremer, B.P.; Sperling, K.R.

    1980-01-01

    The chlorophycean Ulva lactuca L. was grown in the laboratory in unialgal culture to sufficient size so that up to 70 discs, 24 mm in diameter, could be punched out of a single plant. Using such discs, U. lactuca was then tested with various concentrations of Cd under continuous-flow conditions. A concentration of 4.5 ppm Cd was lethal to U. lactuca within 6 days. Control discs in unpolluted water increased in diameter at a rate of 8 to 13% day/sup -1/ over a 6-day period. At sublethal concentration of Cd a sharp reduction in growth rate was observed at increasing concentrations up to approximately 0.3 ppm Cd, whereas from 0.3 ppm Cd to the lethal concentrations the reduction of the growth rate was significantly less. Reduction in photosynthetic performance corresponded closely to the recuction in growth rate. At ambient concentrations of 0.8 ppm Cd, the plants concentrated Cd by a factor of approximately 50 in 6 days. Much higher concentration factors were attained in lower ambient concentrations. After removal from Cd-polluted water into flow-through culture in unpolluted water, a subsequent loss of Cd was indicated and the plants recovered rapidly. Plants exposed up to 3 d to 0.7 ppm Cd recovered sufficiently to produce viable gametes 7 days after removal from Cd. Because it has a relatively short life span and apparently loses Cd subsequent to exposure to Cd-polluted water, Ulva lactuca is not recommended as an alga for monitoring in-situ environmental pollution.

  8. Co-biosorption of copper and glyphosate by Ulva lactuca.

    Science.gov (United States)

    Trinelli, María Alcira; Areco, María Mar; Afonso, María dos Santos

    2013-05-01

    This study investigated the adsorption of glyphosate (PMG) onto the green algae Ulva lactuca. PMG was not adsorbed by U. lactuca but PMG was adsorbed when the process was mediated by Cu(II) with molar ratios Cu(II):PMG≥1.5:1. U. lactuca was characterized by water adsorption surface area, FTIR, SEM and EDS. The Langmuir and Freundlich models were applied. Results showed that the biosorption processes for copper and PMG in the presence of copper were described described by the Langmuir model (qmax=0.85±0.09 mmol g(-1), KL=0.55±0.14 l mmol(-1) and qmax=3.65±0.46 mmol g(-1), KL=0.103±0.03 l mmol(-1), respectively). Copper adsorption was greater in the presence of PMG than in the absence of the pesticide and the adsorption can only be represented by the Freundlich model (KF=0.08±0.01, 1/n=1.86±0.07). In all cases studied, the maximum metal uptake (qmax) increased with increasing pH. Surface complexes with a stoichiometry ranging from ≡Cu-PMG-Cu to ≡Cu-PMG-Cu3 are suggested as reaction products of the process. Due to the increasing amounts of PMG applied in Argentina, natural reservoirs present considerable amounts of this herbicide. The value of this work resides in using U. lactuca, a marine seaweed commonly found along coastlines all over the world, as a biosorbent for PMG. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Synthesis and Electronic Structure of Boron-Graphdiyne with an sp-Hybridized Carbon Skeleton and Its Application in Sodium Storage.

    Science.gov (United States)

    Wang, Ning; Li, Xiaodong; Tu, Zeyi; Zhao, Fuhua; He, Jianjiang; Guan, Zhaoyong; Huang, Changshui; Yi, Yuanping; Li, Yuliang

    2018-04-03

    Boron-graphdiyne (BGDY), which has a unique π-conjugated structure comprising an sp-hybridized carbon skeleton and evenlydistributed boron heteroatoms in a well-organized 2D molecular plane, is prepared through a bottom-up synthetic strategy. Excellent conductivity, a relatively low band gap and a packing mode of the planar BGDY are observed. Notably, the unusual bonding environment of the all sp-carbon framework and the electron-deficient boron centers generates affinity to metal atoms, and thus provides extra binding sites. Furthermore, the expanded molecule pores of the BGDY molecular plane can also facilitate the transfer of metal ions in the perpendicular direction. The practical effect of the all sp-carbon structure and boron heteroatoms on the properties of BGDY are demonstrated in its performance as the anode in sodium-ion batteries. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Enzyme kinetics, inhibitors, mutagenesis and electron paramagnetic resonance analysis of dual-affinity nitrate reductase in unicellular N(2)-fixing cyanobacterium Cyanothece sp. PCC 8801.

    Science.gov (United States)

    Wang, Tung-Hei; Chen, Yung-Han; Huang, Jine-Yung; Liu, Kang-Cheng; Ke, Shyue-Chu; Chu, Hsiu-An

    2011-11-01

    The assimilatory nitrate reductase (NarB) of N(2)-fixing cyanobacterium Cyanothece sp. PCC 8801 is a monomeric enzyme with dual affinity for substrate nitrate. We purified the recombinant NarB of Cyanothece sp. PCC 8801 and further investigated it by enzyme kinetics analysis, site-directed mutagenesis, inhibitor kinetics analysis, and electron paramagnetic resonance (EPR) spectroscopy. The NarB showed 2 kinetic regimes at pH 10.5 or 8 and electron-donor conditions methyl viologen or ferredoxin (Fd). Fd-dependent NR assay revealed NarB with very high affinity for nitrate (K(m)1, ∼1μM; K(m)2, ∼270μM). Metal analysis and EPR results showed that NarB contains a Mo cofactor and a [4Fe-4S] cluster. In addition, the R352A mutation on the proposed nitrate-binding site of NarB greatly altered both high- and low-affinity kinetic components. Furthermore, the effect of azide on the NarB of Cyanothece sp. PCC 8801 was more complex than that on the NarB of Synechococcus sp. PCC 7942 with its single kinetic regime. With 1mM azide, the kinetics of the wild-type NarB was transformed from 2 kinetic regimes to hyperbolic kinetics, and its activity was enhanced significantly under medium nitrate concentrations. Moreover, EPR results also suggested a structural difference between the two NarBs. Taken together, our results show that the NarB of Cyanothece sp. PCC 8801 contains only a single Mo-catalytic center, and we rule out that the enzyme has 2 independent, distinct catalytic sites. In addition, the NarB of Cyanothece sp. PCC 8801 may have a regulatory nitrate-binding site. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  11. Detection of glucose in the growth media of Ulva lactuca using a Ni-Cu/TiO2/Ti self-assembly nanostructure sensor under the influence of crude oil

    Directory of Open Access Journals (Sweden)

    Taghreed Alsufyani

    2017-06-01

    Full Text Available Pollution of the marine environment by crude oil is considered as a significant problem. Interestingly, the existence of algae in the marine ecosystem contributes significantly to maintaining the equilibrium of marine life and, consequently, has the ability to alert the ecosystem to the pollution by using their waterborne molecules including the photosynthetic products. The main aim of this work is to develop an electrochemical sensor (EC for the detection of the concentration of glucose found in the growth media of Ulva sp. as a photosynthetic product or decomposed substance under polluted conditions. A Ni-Cu/TiO2/Ti array electrode was fabricated, where highly-ordered self-organized nanocrystalline TiO2 was prepared via anodization and annealing processes on a Ti substrate and Ni-Cu alloy nanoparticles were electrodeposited by linear sweep voltammetry. The chemical composition, structure and morphology characterization were carried out by high-resolution scanning electron microscopy and energy dispersive X-ray spectroscopy analyses. The ideal non-enzymatic sensor with large and constant sensitivity (402 μA mM−1 cm−2 and low detection limit (495 μM was successfully employed to detect glucose excreted by Ulva lactuca under oil pollution under alkaline condition. The present study succeeded to combine between the ecological role of algae and electrochemical sensors to be used collectively as an indicator of the oil spillage into the seawater.

  12. Genetic dissection of Lactuca saligna nonhost resistance to downy mildew at various lettuce developmental stages

    NARCIS (Netherlands)

    Zhang, N.; Lindhout, P.; Niks, R.E.; Jeuken, M.J.W.

    2009-01-01

    This study used the pathosystem of lettuce (Lactuca spp.) and downy mildew (Bremia lactucae) as a model to investigate the inheritance of nonhost resistance, and focused on the contribution of quantitative trait loci (QTLs) to nonhost resistance at various developmental stages in the lettuce life

  13. Factors affecting the survival of Bremia lactucae sporangia deposited on lettuce leaves

    NARCIS (Netherlands)

    Wu, B.M.; Subbarao, K.V.; Bruggen, van A.H.C.

    2000-01-01

    Experiments to identify the factors affecting survival of Bremia lactucae sporangia after deposition on lettuce leaves were conducted in growth chambers and outdoors under ambient conditions. Lettuce seedlings at the four-leaf stage were inoculated with B. lactucae sporangia under dry conditions.

  14. Usage of ferrum (ІІІ and manganese (IV ions as electron acceptors by Desulfuromonas sp. bacteria

    Directory of Open Access Journals (Sweden)

    O. M. Moroz

    2016-03-01

    Full Text Available The toxicity of metal ions to microorganisms, in particular at high concentrations, is one of the main impediments to their usage in remediation technologies. The purpose of this work is to analyze the possibility of usage by bacteria of the Desulfuromonas genus, isolated by us from Yavorivske Lake, of ferrum (ІІІ and manganese (IV ions at concentrations in the medium of 1,74–10,41 mM as electron acceptors of anaerobic respiration to assesss resistance of sulphur reducing bacteria strains to heavy metal compounds. Cells of Desulfuromonas acetoxidans ІМV V-7384, Desulfuromonas sp. Yavor-5 and Desulfuromonas sp. Yavor-7 were cultivated for 10 days at 30 °C under anaerobic conditions in Kravtsov-Sorokin’s medium without sulphate ions, sulphur, with cysteine as the sulphur source (0.2 g/l and sodium lactate or citrate as the electron donor (17.86 g/l, in which were added sterile 1 M solutions of C6H5O7Fe and C4H4O4 (control and also weights of MnO2 to their terminal concentrations 1.74, 3.47, 5.21, 6.94, 10.41 mM. Biomass was determined by the turbidimetric method. In the culture liquid the presence of Fe3+ and Mn4+ were qualitatively determined, and the content of Fe2+ in reaction with о-phenanthroline was determined quantitatively. It was established that sulphur reducing bacteria used with different intensity ferrum (ІІІ and manganese (IV ions as electron acceptors during the process of anaerobic respiration at concentrations of 1.74–10.41 mM C6H5O7Fe and MnO2 in the medium, which demonstrated the important role of the investigated microorganisms in reductive detoxication of natural and technogenic media from oxidized forms of transitional heavy metals. An insignificant difference in biomass accumulation during usage of 5.21–10.41 mM ferrum (ІІІ ions and fumarate is caused by toxicity of the metal ions to cells since the high redox potential of the Fe(III/Fe(ІІ pair with increase in concentrations of electron acceptors in

  15. Genomic Analysis of Anaerobic Respiration in the Archaeon Halobacterium sp. Strain NRC-1: Dimethyl Sulfoxide and Trimethylamine N-Oxide as Terminal Electron Acceptors†

    OpenAIRE

    Müller, Jochen A.; DasSarma, Shiladitya

    2005-01-01

    We have investigated anaerobic respiration of the archaeal model organism Halobacterium sp. strain NRC-1 by using phenotypic and genetic analysis, bioinformatics, and transcriptome analysis. NRC-1 was found to grow on either dimethyl sulfoxide (DMSO) or trimethylamine N-oxide (TMAO) as the sole terminal electron acceptor, with a doubling time of 1 day. An operon, dmsREABCD, encoding a putative regulatory protein, DmsR, a molybdopterin oxidoreductase of the DMSO reductase family (DmsEABC), and...

  16. The line shape analysis of electron spectroscopy spectra by the artifical intelligence methods for identification of C sp.sup.2./sup./sp.sup.3./sup. bonds

    Czech Academy of Sciences Publication Activity Database

    Lesiak, B.; Zemek, Josef; Jiříček, Petr; Stobinski, L.; Jozwik, A.

    2010-01-01

    Roč. 247, 11-12 (2010), s. 2838-2842 ISSN 0370-1972 R&D Projects: GA ČR GA202/09/0428 Institutional research plan: CEZ:AV0Z10100521 Keywords : carbon nanotubes * temperature functionalization * electron spectroscopy * line shape analysis Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.344, year: 2010

  17. [Analysis of essential oil extracted from Lactuca sativa seeds growing in Xinjiang by GC-MS].

    Science.gov (United States)

    Xu, Fang; Wang, Qiang; Haji, Akber Aisa

    2011-12-01

    To analyze the components of essential oil from Lactuca sativa seeds growing in Xinjiang. The components of essential oil from Lactuca sativa seeds were analyzed by gas chromatography-mass spectrometry (GC-MS). 62 components were identified from 71 separated peaks,amounting to total mass fraction 95.07%. The dominant compounds were n-Hexanol (36.31%), n-Hexanal (13.71%), trans-2-Octen-l-ol (8.09%) and 2-n-Pentylfuran (4.41%). The research provides a theoretical basis for the exploitation and use of Lactuca sativa seeds resource.

  18. ExaSP2

    Energy Technology Data Exchange (ETDEWEB)

    2017-09-08

    ExaSP2 is a reference implementation of typical linear algebra algorithms and workloads for a quantum molecular dynamics (QMD) electronic structure code. The algorithm is based on a recursive second-order Fermi-Operator expansion method (SP2) and is tailored for density functional based tight-binding calculations of material systems.

  19. Characterization at Atomic Resolution of Carbon Nanotube/Resin Interface in Nanocomposites by Mapping sp 2-Bonding States Using Electron Energy-Loss Spectroscopy.

    Science.gov (United States)

    Su, Yi-Feng; Park, Jin G; Koo, Ana; Trayner, Sarah; Hao, Ayou; Downes, Rebekah; Liang, Richard

    2016-06-01

    Functionalization is critical for improving mechanical properties of carbon nanotubes (CNTs)/polymer nanocomposites. A fundamental understanding of the role of the CNT/polymer interface and bonding structure is key to improving functionalization procedures for higher mechanical performance. In this study, we investigated the effects of chemical functionalization on the nanocomposite interface at atomic resolution to provide direct and quantifiable information of the interactions and interface formation between CNT surfaces and adjacent resin molecules. We observed and compared electronic structures and their changes at the interfaces of nonfunctionalized and functionalized CNT/polymer nanocomposite samples via scanning transmission electron microscopy and electron energy-loss spectroscopy (EELS) spectrum imaging techniques. The results show that the state of sp 2 bonding and its distribution at the CNT/resin interface can be clearly visualized through EELS mapping. We found that the functionalized CNT/polymer samples exhibited a lower fraction of sp 2 bonding and a lower π*/σ* ratio compared with the nonfunctionalized cases. A good correlation between near-edge fine structures and low-loss plasmon energies was observed.

  20. Bioenergy potential of Ulva lactuca: Biomass yield, methane production and combustion

    DEFF Research Database (Denmark)

    Bruhn, Annette; Dahl, Jonas; Bangsø Nielsen, Henrik

    2011-01-01

    The biomass production potential at temperate latitudes (56°N), and the quality of the biomass for energy production (anaerobic digestion to methane and direct combustion) were investigated for the green macroalgae, Ulva lactuca. The algae were cultivated in a land based facility demonstrating...... a production potential of 45 T (TS) ha−1 y−1. Biogas production from fresh and macerated U. lactuca yielded up to 271 ml CH4 g−1 VS, which is in the range of the methane production from cattle manure and land based energy crops, such as grass-clover. Drying of the biomass resulted in a 5–9-fold increase...... in weight specific methane production compared to wet biomass. Ash and alkali contents are the main challenges in the use of U. lactuca for direct combustion. Application of a bio-refinery concept could increase the economical value of the U. lactuca biomass as well as improve its suitability for production...

  1. Facile green synthesis of zinc oxide nanoparticles using Ulva lactuca seaweed extract and evaluation of their photocatalytic, antibiofilm and insecticidal activity.

    Science.gov (United States)

    Ishwarya, Ramachandran; Vaseeharan, Baskaralingam; Kalyani, Subramanian; Banumathi, Balan; Govindarajan, Marimuthu; Alharbi, Naiyf S; Kadaikunnan, Shine; Al-Anbr, Mohammed N; Khaled, Jamal M; Benelli, Giovanni

    2018-01-01

    The bioactivity of semiconductor nanocomplexes has been poorly studied in the field of pesticide science. In this research, the synthesis of zinc nanoparticles was accomplished through new effortless green chemistry process, using the Ulva lactuca seaweed extract as a reducing and capping agent. The production of U. lactuca-fabricated ZnO nanoparticles (Ul-ZnO Nps) was characterized by powder X-ray diffraction (XRD), UV-visible, Fourier transform infrared (FTIR) spectroscopy, selected area electron diffraction (SAED) analysis and transmission electron microscopy (TEM). The U. lactuca-fabricated ZnO NPs were tested for their photodegradative action against organic dyes, as well as for antibiofilm and larvicidal activities. The UV visible absorbance spectrum of Ul-ZnO NPs exhibited the absorbance band at 325nm and TEM highlighted average crystallite sizes of nanoparticles of 10-50nm. Methylene blue (MB) dye was efficiently corrupted under sunlight in presence of Ul-ZnO NPs. Excellent bactericidal activity was shown by the Ul-ZnO Nps on Gram positive (Bacillus licheniformis and Bacillus pumilis) and Gram negative (Escherichia coliand Proteus vulgaris) bacteria. High antibiofilm potential was noted under both dark and sunlight conditions. The impact of a single treatment with Ul-ZnO NPs on biofilm architecture was also analyzed by confocal laser scanning microscopy (CLSM) on both Gram positive and Gram negative bacteria. Moreover, Ul-ZnO NPs led to 100% mortality of Aedes aegypti fourth instar larvae at the concentration of 50μg/ml within 24h. The effects of ZnO nanoparticle-based treatment on mosquito larval morphology and histology were monitored. Overall, based on our results, we believe that the synthesis of multifunctional Ul-ZnO Nps using widely available seaweed products can be promoted as a potential eco-friendly option to chemical methods currently used for nanosynthesis of antimicrobials and insecticides. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Iterative diagonalization of the non-Hermitian transcorrelated Hamiltonian using a plane-wave basis set: Application to sp-electron systems with deep core states

    Energy Technology Data Exchange (ETDEWEB)

    Ochi, Masayuki, E-mail: ochi@phys.sci.osaka-u.ac.jp; Arita, Ryotaro [RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198 (Japan); JST ERATO Isobe Degenerate pi-Integration Project, Advanced Institute for Materials Research (AIMR), Tohoku University, Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Yamamoto, Yoshiyuki [Department of Physics, The University of Tokyo, Hongo, Bunkyo, Tokyo 113-0033 (Japan); Tsuneyuki, Shinji [Department of Physics, The University of Tokyo, Hongo, Bunkyo, Tokyo 113-0033 (Japan); Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581 (Japan)

    2016-03-14

    We develop an iterative diagonalization scheme in solving a one-body self-consistent-field equation in the transcorrelated (TC) method using a plane-wave basis set. Non-Hermiticity in the TC method is well handled with a block-Davidson algorithm. We verify that the required computational cost is efficiently reduced by our algorithm. In addition, we apply our plane-wave-basis TC calculation to some simple sp-electron systems with deep core states to elucidate an impact of the pseudopotential approximation to the calculated band structures. We find that a position of the deep valence bands is improved by an explicit inclusion of core states, but an overall band structure is consistent with a regular setup that includes core states into the pseudopotentials. This study offers an important understanding for the future application of the TC method to strongly correlated solids.

  3. Halogenated auxins affect microtubules and root elongation in Lactuca sativa

    Science.gov (United States)

    Zhang, N.; Hasenstein, K. H.

    2000-01-01

    We studied the effect of 4,4,4-trifluoro-3-(indole-3-)butyric acid (TFIBA), a recently described root growth stimulator, and 5,6-dichloro-indole-3-acetic acid (DCIAA) on growth and microtubule (MT) organization in roots of Lactuca sativa L. DCIAA and indole-3-butyric acid (IBA) inhibited root elongation and depolymerized MTs in the cortex of the elongation zone, inhibited the elongation of stele cells, and promoted xylem maturation. Both auxins caused the plane of cell division to shift from anticlinal to periclinal. In contrast, TFIBA (100 micromolar) promoted elongation of primary roots by 40% and stimulated the elongation of lateral roots, even in the presence of IBA, the microtubular inhibitors oryzalin and taxol, or the auxin transport inhibitor naphthylphthalamic acid. However, TFIBA inhibited the formation of lateral root primordia. Immunostaining showed that TFIBA stabilized MTs orientation perpendicular to the root axis, doubled the cortical cell length, but delayed xylem maturation. The data indicate that the auxin-induced inhibition of elongation and swelling of roots results from reoriented phragmoplasts, the destabilization of MTs in elongating cells, and promotion of vessel formation. In contrast, TFIBA induced promotion of root elongation by enhancing cell length, prolonging transverse MT orientation, delaying cell and xylem maturation.

  4. Isolation and culture of protoplast from leaves of Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Witool Chaipakdee

    2007-07-01

    Full Text Available Protoplasts were isolated from leaves of lettuce (Lactuca sativa L. seedlings after in vitro germination for 25, 30, 40 and 50 days. The leaves were stripped and incubated in various combinations of cellulase and pectinase. Protoplasts were cultured on MS medium containing various kinds and concentrations of plant growth regulators in different culture systems including liquid media, hanging, drop culture and solid media. Results revealed that the highest number of viable protoplasts, 14.1x105 cells per gram of fresh weight, was obtained from 30 day-old leaves of lettuce seedlings and isolated by using 2% cellulase in combination with 1% pectinase. Liquid MS medium supplemented with 0.5 mg/l NAA and 0.5 mg/l BA promoted the highest cell division up to 17.67%. First division of protoplasts was observed at 4 days after culture and microcolony formation occurred at the 4th week after culturing. Unfortunately, neither callus formation nor plantlet regeneration were obtained.

  5. Initiation and elongation of lateral roots in Lactuca sativa

    Science.gov (United States)

    Zhang, N.; Hasenstein, K. H.

    1999-01-01

    Lactuca sativa cv. Baijianye seedlings do not normally produce lateral roots, but removal of the root tip or application of auxin, especially indole-butyric acid, triggered the formation of lateral roots. Primordia initiated within 9 h and were fully developed after 24 h by activating the pericycle cells opposite the xylem pole. The pericycle cells divided asymmetrically into short and long cells. The short cells divided further to form primordia. The effect of root tip removal and auxin application was reversed by 6-benzylaminopurine at concentrations >10(-8) M. The cytokinin oxidase inhibitor N1-(2chloro4pyridyl)-N2-phenylurea also suppressed auxin-induced lateral rooting. The elongation of primary roots was promoted by L-alpha-(2-aminoethoxyvinyl) glycine and silver ions, but only the latter enhanced elongation of lateral roots. The data indicate that the induction of lateral roots is controlled by basipetally moving cytokinin and acropetally moving auxin. Lateral roots appear to not produce ethylene.

  6. Potentiating Effects of Lactuca sativa on Pentobarbital-Induced Sleep.

    Science.gov (United States)

    Ghorbani, Ahmad; Rakhshandeh, Hassan; Sadeghnia, Hamid Reza

    2013-01-01

    Traditionally, Lactuca sativa (lettuce) has been recommended for its hypnotic property. The present study was planned to investigate sleep-prolonging effect of this plant. The hydro-alcoholic extract (HAE) of lettuce and its water fraction (WF), ethyl acetate fraction (EAF), and n-butanol fraction (NBF) were administrated (IP) to mice 30 min before the pentobarbital injection. Moreover, both in-vivo and in-vitro toxicity of the extracts were determined. The quality of HAE and NBF was also evaluated using HPLC fingerprint. The HAE prolonged the pentobarbital-induced sleep duration at dose of 400 mg/Kg. The NBF was the only fraction which could increase the sleep duration and decrease sleep latency. The effects of NBF were comparable to those of induced by diazepam. The LD50-value for HAE was found to be 4.8 g/Kg. No neurotoxic effect was observed either by HAE or by its fractions in cultured PC12 neuron-like cells. The results suggest that lettuce potentiates pentobarbital hypnosis without major toxic effect. The main component(s) responsible for this effect is most likely to be non-polar agent(s) which found in NBF of this plant.

  7. Marine biomass research in Florida. [Gracilaria tikvahiae, Ulva Lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Ryther, J.H.

    1983-01-01

    The red alga Gracilaria tikvahiae may be grown outdoors year-round in central Florida with yields averaging 35.5 g dry weight/sq. m/day, greater than the most productive terrestrial plants. This occurs when the plants are grown in suspended culture, with vigorous aeration and an exchange of 25 or more culture volumes of enriched seawater per day. A culture system was designed in which Gracilaria, stocked at a density of 2 kg wet weight/sq.m, grows to double its biomass in one to two weeks; it is then harvested to its starting density, and anaerobically digested to methane. The biomass is soaked for 6 hours in the digester residue, storing enough nutrients for two week's growth in unenriched seawater. The methane is combusted for energy and the waste gas is fed to the culture to provide mixing of CO/sub 2/ eliminating the need for aeration and seawater exchange. The green alga Ulva lactuca, unlike Gracilaria, uses bicarbonate as a photosynthesis carbon source, and can be grown at high pH, with little or no free CO/sub 2/. It can therefore produce higher yields than Gracilaria in low water exchange conditions. It is also more efficiently converted to methane than is Gracilaria, but cannot tolerate Florida's summer temperatures so cannot be grown year-round. Attempts are being made to locate or produce through selective breeding, a high-temperature tolerant strain of Ulva. 21 references.

  8. Anxiolytic property of hydro-alcohol extract of Lactuca sativa and its effect on behavioral activities of mice.

    Science.gov (United States)

    Harsha, Singapura Nagesh; Anilakumar, Kandangath Raghavan

    2013-01-01

    Lactuca sativa, belonging to the Asteraceae family, is a leafy vegetable known for its medicinal properties. This study aimed to understand the mechanism of Lactuca sativa extract with respect to pharmacological action.We investigated the anxiolytic effects of hydro-alcoholic extract of leaves of Lactuca sativa on mice. The behavioral tests performed on mice models to assess anti-anxiety properties were: open field test (OFT), elevated plus maze test (EPM), elevated T maze test, and marble burying test. Increased locomotor activity and time spent in the "open-arm" were observed in extract fed group. Malondialdehyde (MDA) and nitrite levels were decreased, catalase and glutathione levels were increased in Lactuca sativa treated mice. The data obtained in the present study suggests that the extract of Lactuca sativa can afford significant protection against anxiolytic activity.

  9. Subsequent influences of feeding intact green seaweed Ulva lactuca to growing lambs on the seminal and testicular characteristics in rams.

    Science.gov (United States)

    Samara, E M; Okab, A B; Abdoun, K A; El-Waziry, A M; Al-Haidary, A A

    2013-12-01

    The present experiment was designed to investigate the subsequent influences of supplementing different levels of intact green seaweed Ulva lactuca (0%, 3%, and 5% DM) to growing sexually immature lambs during the growth period (74 d) on the seminal and testicular characteristics of sexually mature rams. Ulva lactuca was manually collected, adequately prepared, and then incorporated into lambs' diets. Eighteen male 3-mo-old lambs of the Awassi breed with a mean BW of 22.57 kg (SD = 1.08) were randomly assigned into treatments. The obtained results indicate that offering Ulva lactuca at the level of 3% or 5% DM to lambs during the growth period had no subsequent impacts (P > 0.05) on liver and kidney functions as well as blood water balance in rams, thereby suggesting that Ulva lactuca can be safely supplemented to lambs during growing. However, our findings point out that feeding a lamb diet supplemented with intact Ulva lactuca failed to demonstrate any subsequent benefit (P > 0.05) on the growth performance, thermoregulatory responses, and plasma oxidative status in rams. Above all, it was clearly evident that supplementing intact Ulva lactuca to lambs had demonstrated subsequent negative influences (P Ulva lactuca during the growth period compared to control rams. The deleterious impacts of feeding intact Ulva lactuca on spermatogenesis and germ cell loss were proven to be attributed to the dysfunction of Sertoli cells. Collectively, these results provide novel insights on the subsequent influences of dietary supplementation of intact Ulva lactuca to lambs. The consistent evidence of profound negative impacts on seminal and testicular characteristics as well as the resulting data of no improvement of subsequent growth, thermoregulation, and plasma oxidative status in rams prompts us to tentatively recommend the avoidance of feeding intact Ulva lactuca to lambs.

  10. A taxonomic revision of the genus lactuca L. (cicihorieae- asteraceae) from Pakistan and Kashmir

    International Nuclear Information System (INIS)

    Qaiser, M.; Bano, R.

    2011-01-01

    The genus Lactuca L. of the tribe Cichorieae-Asteraceae is taxonomically revised from Pakistan and Kashmir. The revision is based on study of large number of herbarium specimens. In few cases plants have also been studied in their natural habitat. A total of 13 species are recognized from Pakistan and Kashmir including 1 new species i.e. Lactuca erostrata Roohi Bano and Qaiser. A new combination Lactuca orientalis subsp. nuristanica (Podlech) Roohi Bano and Qaiser is also proposed. All the taxa valid or synonyms have been typified with the help of type specimens and literature. Key to the species along with detailed morphological description and ecological notes of each taxon are also given. (author)

  11. Enhancing methane production from U. lactuca using combined anaerobically digested sludge (ADS) and rumen fluid pre-treatment and the effect on the solubilization of microbial community structures.

    Science.gov (United States)

    Zou, Yu; Xu, Xiaochen; Li, Liang; Yang, Fenglin; Zhang, Shushen

    2018-04-01

    Methane production by the anaerobic digestion of seaweed is restricted by the slow degradation caused by the influence of the rigid algal cell wall. At the present time, there has been no study focusing on the anaerobic digestion of U. lactuca by co-fermentation and pre-treatment with rumen fluid. Rumen fluid can favor methane production from algal biomass by utilizing the diversity and quantity of bacterial and archaeal communities in the rumen fluid. This research presents a novel method based on combined ADS and rumen fluid pre-treatment to improve the production of methane from seaweed. Biochemical methane potential (BMP) tests were performed to investigate the biogas production using combined ADS and rumen fluid pre-treatment at varied inoculum ratios on the performance of methane production from U. lactuca biomass. Compared to the control (no rumen fluid pre-treatment), the highest BMP yields of U. lactuca increased from 3%, 27.5% and 39.5% to 31.1%, 73% and 85.6%, respectively, for three different types of treatment. Microbial community analysis revealed that the Methanobrevibacter species, known to accept electrons to form methane, were only detected when rumen fluid was added. Together with the significant increase in species of Methanoculleus, Methanospirillum and Methanosaeta, rumen fluid improved the fermentation and degradation of the microalgae biomass not only by pre-treatment to foster cell-wall degradation but also by relying on methane production within itself during anaerobic processes. Batch experiments further indicated that rumen fluid applied to the co-fermentation and pre-treatment could increase the economic value and hold promise for enhancing biogas production from different seaweed species. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Effector identification in the lettuce downy mildew Bremia lactucae by massively parallel transcriptome sequencing.

    Science.gov (United States)

    Stassen, Joost H M; Seidl, Michael F; Vergeer, Pim W J; Nijman, Isaäc J; Snel, Berend; Cuppen, Edwin; Van den Ackerveken, Guido

    2012-09-01

    Lettuce downy mildew (Bremia lactucae) is a rapidly adapting oomycete pathogen affecting commercial lettuce cultivation. Oomycetes are known to use a diverse arsenal of secreted proteins (effectors) to manipulate their hosts. Two classes of effector are known to be translocated by the host: the RXLRs and Crinklers. To gain insight into the repertoire of effectors used by B. lactucae to manipulate its host, we performed massively parallel sequencing of cDNA derived from B. lactucae spores and infected lettuce (Lactuca sativa) seedlings. From over 2.3 million 454 GS FLX reads, 59 618 contigs were assembled representing both plant and pathogen transcripts. Of these, 19 663 contigs were determined to be of B. lactucae origin as they matched pathogen genome sequences (SOLiD) that were obtained from >270 million reads of spore-derived genomic DNA. After correction of cDNA sequencing errors with SOLiD data, translation into protein models and filtering, 16 372 protein models remained, 1023 of which were predicted to be secreted. This secretome included elicitins, necrosis and ethylene-inducing peptide 1-like proteins, glucanase inhibitors and lectins, and was enriched in cysteine-rich proteins. Candidate host-translocated effectors included 78 protein models with RXLR effector features. In addition, we found indications for an unknown number of Crinkler-like sequences. Similarity clustering of secreted proteins revealed additional effector candidates. We provide a first look at the transcriptome of B. lactucae and its encoded effector arsenal. © 2012 THE AUTHORS. MOLECULAR PLANT PATHOLOGY © 2012 BSPP AND BLACKWELL PUBLISHING LTD.

  13. Identification and characterization of a library of surfactins and fengycins from a marine endophytic Bacillus sp.

    Science.gov (United States)

    Nair, Divya; Vanuopadath, Muralidharan; Nair, Bipin G; Pai, Jayashree Gopalakrishna; Nair, Sudarslal Sadasivan

    2016-11-01

    An endophytic bacterial strain from a marine green alga, Ulva lactuca, was isolated and identified by 16S rRNA gene sequencing method. The bacterial isolate was found to secrete two major families of cyclic depsilipopeptides, surfactins, and fengycins. Sequencing of the isolated lipopeptides was carried out using the MS n data obtained from an electrospray ionization (ESI) ion trap mass spectrometer coupled to an HPLC system. The assigned sequences were confirmed by a chemical derivatization approach involving esterification followed by mass spectrometric analysis. Distinction of leucine residues from isoleucine was established through a combined electron transfer dissociation-collision-induced dissociation (ETD-CID) method. The fengycins described in this study were found to cause significant delay of growth of two plants, Vigna radiata (mung bean) and Oryza sativa (rice). To the best of our knowledge, this is the first study describing identification and characterization of cyclic peptides from an endophytic Bacillus sp. isolated from marine algae. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Pb low doses induced genotoxicity in Lactuca sativa plants.

    Science.gov (United States)

    Silva, S; Silva, P; Oliveira, H; Gaivão, I; Matos, M; Pinto-Carnide, O; Santos, C

    2017-03-01

    Soil and water contamination by lead (Pb) remains a topic of great concern, particularly regarding crop production. The admissible Pb values in irrigation water in several countries range from ≈0.1 to ≈5 mg L -1 . In order to evaluate putative effects of Pb within legal doses on crops growth, we exposed Lactuca sativa seeds and seedlings to increasing doses of Pb(NO 3 ) 2 up to 20 mg L -1 . The OECD parameter seed germination and seedling/plant growth were not affected by any of the Pb-concentrations used. However, for doses higher than 5 mg L -1 significant DNA damage was detected: Comet assay detected DNA fragmentation at ≥ 5 mg L -1 and presence of micronuclei (MN) were detected for 20 mg L -1 . Also, cell cycle impairment was observed for doses as low as 0.05 mg L -1 and 0.5 mg L -1 (mostly G 2 arrest). Our data show that for the low doses of Pb used, the OECD endpoints were not able to detect toxicity, while more sensitive endpoints (related with DNA damage and mitotic/interphase disorders) identified genotoxic and cytostatic effects. Furthermore, the nature of the genotoxic effect was dependent on the concentration. Finally, we recommend that MN test and the comet assay should be included as sensitive endpoints in (eco)toxicological assays. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  15. Ionizing radiation from {sup 60}Co and electron accelerator in reducing the population of Salmonella sp. inoculated in chicken meatballs: evaluation of acceptance by consumer;Radiacoes ionizantes provenientes de {sup 60}CO e acelerador de eletrons na reducao da populacao de Salmonella sp. inoculada em almondegas de frango: avaliacao da aceitacao do produto pelo consumidor

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Juliana

    2003-07-01

    Salmonella sp. is one of the main microorganisms that causes outbreaks of food borne diseases associated to poultry, and among its derivatives, the chicken meatballs are getting the favorites of the consumer. In the attempt to improve microbiological food safety, a method that has been hardly studied is the irradiation. To study the viability of the use o ionizing radiation originated from {sup 60} Co and electrons accelerator in the reduction of Salmonella sp., frozen chickens meatballs were inoculated with 10{sup 4} CFU/g of Salmonella sp., with needle and syringe. Subsequently they were exposure to doses of 1.5, 2.0, 2.5 and 3.0 kGy and Salmonella sp. was enumerated. Chicken meatballs were exposed to doses 3.0, 4.0 and 5.0 kGy and submitted to sensory analysis. The gamma radiation from {sup 60}CO was effective in the reduction of Salmonella sp. inoculated in chicken meatballs. The ionizing radiation originated from electron beam was not effective in the conditions applied in this research. The commercial chicken meatballs prepared with chicken meat, mixed up with soy protein, seasoning and anti-oxidants additives did not loose their sensorial quality when exposure to doses of 3.0, 4.0 and 5.0 kGy and, in a general way, the consumers showed to be disposed to buy the irradiation product (author)

  16. Estimation of Folate (Vitamin B9) in fresh Lactuca sativa (Lettuce ...

    African Journals Online (AJOL)

    An attempt was made to extract and estimate Vitamin B9 (folate) from 3 different vegetables namely Lactuca sativa (Lettuce), Spinacia oleracea (Spinach) and Brassica oleracea (Cabbage) from four locations using dibasic potassium phosphate at a temperature of 60 ° UV double beam spectrophotometer was used to ...

  17. Phosphomannose isomerase gene for selection in lettuce (Lactuca sativa L.) transformation

    Czech Academy of Sciences Publication Activity Database

    Bříza, Jindřich; Růžičková, N.; Niedermeierová, Hana; Dusbábková, Jana; Vlasák, Josef

    2010-01-01

    Roč. 57, č. 1 (2010), s. 63-68 ISSN 0001-527X Institutional research plan: CEZ:AV0Z50510513 Keywords : pmi * npt II * Lactuca sativa Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.234, year: 2010

  18. Plant Age Affects Wound-Induced Senescense in Lactuca Sativa L

    NARCIS (Netherlands)

    Witkowska, I.M.; Woltering, E.J.

    2014-01-01

    In the present study we investigated the performance of dark-stored wounded leaf discs and pieces (to some extent mimicking fresh-cut product) of Lactuca sativa L. in relation to the physiological maturity at harvest. We used two related genotypes, i.e. a green (cv. Troubadour) and a red butterhead

  19. Differential growth response of Ulva lactuca to ammonium and nitrate assimilation

    DEFF Research Database (Denmark)

    Ale, Marcel Tutor; Mikkelsen, Jørn Dalgaard; Meyer, Anne S

    2011-01-01

    Controlled cultivation of marine macroalgal biomass such as Ulva species, notably Ulva lactuca, is currently studied for production of biofuels or functional food ingredients. In a eutrophic environment, this macrophyte is exposed to varying types of nutrient supply, including different and fluct...

  20. Species relationships in Lactuca S.L. (Lactuceae, Asteraceae) inferred from AFLP fingerprints

    NARCIS (Netherlands)

    Koopman, W.J.M.; Zevenbergen, M.J.; Berg, van den R.G.

    2001-01-01

    An AFLP data set comprising 95 accessions from 20 species of Lactuca s.l. (sensu lato) and related genera was generated using the primer combinations E35/M48 and E35/M49. In phenetic analyses of a data subset, clustering with UPGMA based on Jaccard's similarity coefficient resulted in the highest

  1. Robustness and accuracy of Maxent niche modelling for Lactuca species distributions in light of collecting expeditions

    NARCIS (Netherlands)

    Cobben, M.M.P.; van Treuren, R.; Castañeda-Álvarez, N.P.; Khoury, C.K.; Kik, C.; van Hintum, T.J.L.

    2015-01-01

    Niche modelling software can be used to assess the probability of detecting a population of a plant species at a certain location. In this study, we used the distribution of the wild relatives of lettuce (Lactuca spp.) to investigate the applicability of Maxent species distribution models for

  2. Molecular biogeography of prickly lettuce (Lactuca serriola L.) shows traces of recent range expansion

    NARCIS (Netherlands)

    D'Andrea, L.; Meirmans, P.G.; van de Wiel, C.; Guadagnuolo, R.; van Treuren, R.; Kozlowski, G.; den Nijs, H.; Felber, F.

    2017-01-01

    Prickly lettuce (Lactuca serriola L., Asteraceae), a wild relative of cultivated lettuce, is an autogamous species which greatly expanded throughout Western and Northern Europe during the last 2 centuries. Here, we present a large-scale biogeographic genetic analysis performed on a dataset

  3. Effector identification in the lettuce downy mildew Bremia lactucae by massively parallel transcriptome sequencing

    NARCIS (Netherlands)

    Stassen, J.H.; Seidl, M.F.; Vergeer, P.W.; Nijman, I.J.; Snel, B.; Cuppen, E.; van den Ackerveken, G.

    2012-01-01

    Lettuce downy mildew (Bremia lactucae) is a rapidly adapting oomycete pathogen affecting commercial lettuce cultivation. Oomycetes are known to use a diverse arsenal of secreted proteins (effectors) to manipulate their hosts. Two classes of effector are known to be translocated by the host: the

  4. Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L.) cultivars and mapping genes

    Science.gov (United States)

    Background: Lettuce (Lactuca sativa L.) is the major vegetable from the group of leafy vegetables. Several types of molecular markers were developed that are effictively used in lettuce breeding and genetic studies. However only a very limited number of microsattelite-based markers are publicly avai...

  5. Effect of mancozeb-treated lettuce ( Lactuca sativa ) on wistar rat liver

    African Journals Online (AJOL)

    Because mancozeb, ethylene bis-dithiocarbamate, is mainly used, more than five times, during the growth of lettuce (Lactuca sativa), the aim of the present investigation is to evaluate the potential effect of mancozeb-treated lettuce on the rat liver physiology. Mancozeb-treated lettuce and two doses of mancozeb were ...

  6. Production of acetone, butanol, and ethanol from biomass of the green seaweed Ulva lactuca

    NARCIS (Netherlands)

    Wal, van der H.; Sperber, B.L.H.M.; Houweling-Tan, G.B.N.; Bakker, R.R.C.; Brandenburg, W.A.; Lopez Contreras, Ana

    2013-01-01

    Green seaweed Ulva lactuca harvested from the North Sea near Zeeland (The Netherlands) was characterized as feedstock for acetone, ethanol and ethanol fermentation. Solubilization of over 90% of sugars was achieved by hot-water treatment followed by hydrolysis using commercial cellulases. A

  7. Evaluation of Nutritional Composition of The Dried Seaweed Ulva lactuca from Pameungpeuk Waters, Indonesia.

    Science.gov (United States)

    Rasyid, Abdullah

    2017-07-01

    The nutritional composition of the dried seaweed Ulva lactuca from Pameungpeuk waters, including proximate, vitamins, minerals, dietary fibre and heavy metal has been carried out. The objective of this present study is to know the nutritional composition of the dried seaweed U. lactuca for utilisation in human nutrition in the future. Results show that carbohydrate was the major component in the proximate analysis of U. lactuca in the present study. The carbohydrate content was 58.1%. Moisture, ash, protein and fat content were 16.9%, 11.2%, 13.6% and 0.19% respectively, while dietary fibre was 28.4%. The vitamin A content was examined in this study less than 0.5 IU/100 mg while vitamin B1 (thiamine) and vitamin B2 (riboflavin) were 4.87 mg/kg and 0.86 mg/kg respectively. The calcium content was 1828 mg/100 g higher than other minerals. The heavy metal content examined in this study were lower than the limit of the quality criteria applied to edible seaweeds sold in Indonesia. Based on the results of this study show that U. lactuca has potential to be developed as an alternative source of a healthy food for human in the future.

  8. USE OF ULVA LACTUCA TO DISTINGUISH PH DEPENDENT TOXICANTS IN MARINE WATERS AND SEDIMENTS

    Science.gov (United States)

    Ulva lactuca (sea lettuce) is a cosmopolitan marine attached green seaweed capable of sequestering high environmental levels of ammonia. Ammonia can be acutely toxic to marine organisms and is often found in dredged sediments from highly industrial areas or from areas with high c...

  9. Biorefinery of the green seaweed Ulva lactuca to produce animal feed, chemicals and biofuels.

    Science.gov (United States)

    Bikker, Paul; van Krimpen, Marinus M; van Wikselaar, Piet; Houweling-Tan, Bwee; Scaccia, Nazareno; van Hal, Jaap W; Huijgen, Wouter J J; Cone, John W; López-Contreras, Ana M

    2016-01-01

    The growing world population demands an increase in animal protein production. Seaweed may be a valuable source of protein for animal feed. However, a biorefinery approach aimed at cascading valorisation of both protein and non-protein seaweed constituents is required to realise an economically feasible value chain. In this study, such a biorefinery approach is presented for the green seaweed Ulva lactuca containing 225 g protein ( N  × 4.6) kg -1 dry matter (DM). The sugars in the biomass were solubilised by hot water treatment followed by enzymatic hydrolysis and centrifugation resulting in a sugar-rich hydrolysate (38.8 g L -1 sugars) containing glucose, rhamnose and xylose, and a protein-enriched (343 g kg -1 in DM) extracted fraction. This extracted fraction was characterised for use in animal feed, as compared to U. lactuca biomass. Based on the content of essential amino acids and the in vitro N (85 %) and organic matter (90 %) digestibility, the extracted fraction seems a promising protein source in diets for monogastric animals with improved characteristics as compared to the intact U. lactuca . The gas production test indicated a moderate rumen fermentation of U. lactuca and the extracted fraction, about similar to that of alfalfa. Reduction of the high content of minerals and trace elements may be required to allow a high inclusion level of U. lactuca products in animal diets. The hydrolysate was used successfully for the production of acetone, butanol, ethanol and 1,2-propanediol by clostridial fermentation, and the rhamnose fermentation pattern was studied.

  10. SSH reveals a linkage between a senescence-associated protease and Verticillium wilt symptom development in lettuce (Lactuca sativa)

    Science.gov (United States)

    Suppression subtractive hybridization (SSH) was employed to identify lettuce (Lactuca sativa) genes that are differentially expressed in symptomatic leaves infected with Verticillium dahliae. Genes expressed only in symptomatic leaves included those with homology to pathogenesis-related (PR) protei...

  11. Decontamination treatments to eliminate problem biota from macroalgal tank cultures of Osmundea pinnatifida, Palmaria palmata and Ulva lactuca

    OpenAIRE

    Kerrison, Philip D.; Le, Hau Nhu; Twigg, Gail C.; Smallman, Duncan R.; MacPhee, Rory; Houston, Fiona A. B.; Hughes, Adam D.

    2016-01-01

    The effect of a range of chemical disinfectants at different concentration and exposure times was investigated on five macroalgal species and the marine gastropod Littorina spp. Palmaria palmata, Osmundea pinnatifida and Ulva lactuca are commercially valuable and are often cultivated in tanks for food or feed. Ectocarpus siliculosus and Ulva intestinalis are common epiphytes of P. palmata and O. pinnatifida cultures, whilst Littorina spp. are common herbivorous epibionts within U. lactuca cul...

  12. Root constituents of Lactuca sibirica and a comparison of metabolite profiles of L. sibirica and L. tatarica

    Directory of Open Access Journals (Sweden)

    Wanda Kisiel

    2011-01-01

    Full Text Available Nine known sesquiterpene lactones, including four lactucin-type guaianolides, four costuslactone-type guaianolides and one germacranolide, were isolated from roots of Lactuca sibirica (Asteraceae, six of which were glycoside derivatives. The chemosystematic significance of the compounds is discussed in the context of sesquiterpenoids present in roots of the closely related species Lactuca tatarica. A comparison of sesquiterpene lactone profiles indicate that the species can be differentiated on the basis of their germacranolide glycoside compositions.

  13. Use of seaweed Ulva lactuca for water bioremediation and as feed additive for white shrimp Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Regina Elizondo-González

    2018-03-01

    Full Text Available Two experimental feeding trials were conducted during four weeks to evaluate the use of Ulva lactuca in shrimp culture: (1 for wastewater bioremediation, and (2 using different inclusion levels of U. lactuca meal in shrimp feed. In feeding trial 1, shrimp reared under seaweed U. lactuca water exchange in a re-circulation system (SWE resulted in similar growth and feed utilization as shrimp reared with clean water exchange (CWE. Shrimp under no water exchange (NWE resulted in significant lower growth and higher feed conversion rate (FCR compared to the other treatments (p  0.05. In feeding trial 2, U. lactuca biomass produced by wastewater bioremediation in SWE treatment were dried and ground to formulate diets containing 0, 1, 2, and 3% U. lactuca meal (0UL, 1UL, 2UL, and 3UL. Shrimp fed the 3 UL diet resulted in a significant (p < 0.05 improvement of growth and FCR, and enhanced whole shrimp lipid and carotenoid content by 30 and 60%, respectively, compared to control diet. Seaweed U. lactuca is suggested as a desirable species for wastewater bioremediation in integrated aquaculture systems, and its meal as a good feed additive for farmed shrimp.

  14. Use of seaweed Ulva lactuca for water bioremediation and as feed additive for white shrimp Litopenaeus vannamei.

    Science.gov (United States)

    Elizondo-González, Regina; Quiroz-Guzmán, Eduardo; Escobedo-Fregoso, Cristina; Magallón-Servín, Paola; Peña-Rodríguez, Alberto

    2018-01-01

    Two experimental feeding trials were conducted during four weeks to evaluate the use of Ulva lactuca in shrimp culture: (1) for wastewater bioremediation, and (2) using different inclusion levels of U. lactuca meal in shrimp feed. In feeding trial 1, shrimp reared under seaweed U. lactuca water exchange in a re-circulation system (SWE) resulted in similar growth and feed utilization as shrimp reared with clean water exchange (CWE). Shrimp under no water exchange (NWE) resulted in significant lower growth and higher feed conversion rate (FCR) compared to the other treatments ( p   0.05). In feeding trial 2, U. lactuca biomass produced by wastewater bioremediation in SWE treatment were dried and ground to formulate diets containing 0, 1, 2, and 3% U. lactuca meal (0UL, 1UL, 2UL, and 3UL). Shrimp fed the 3 UL diet resulted in a significant ( p  Seaweed U. lactuca is suggested as a desirable species for wastewater bioremediation in integrated aquaculture systems, and its meal as a good feed additive for farmed shrimp.

  15. Morphological description of Cosmocerca sp. (Nematoda: Cosmocerdidae) from the Mascarene grass frog Ptychadena cf. mascareniensis (Amphibia: Ptychadenidae). A light and scanning electron microscopic studies.

    Science.gov (United States)

    Abdel-Gaber, Rewaida; Abdel-Ghaffar, Fathy; Kamel, Reem; Maher, Sherein; El Deeb, Nashwa; Al Quraishy, Saleh; Mehlhorn, Heinz

    2017-06-01

    The Mascarene grass frog Ptychadena cf. mascareniensis is a species of frog with a vast area of distribution in Africa. A total of 300 frog specimens were collected from different localities at El-Giza province, Egypt; then dissected and examined for the presence of parasitic infection. Only eighty six (28.66%) specimens were found to be naturally infected with nematode parasite. Seasonally, the prevalence of infection was reached its maximum value of 74.66% during summer and minimum values of 26.66% (20/75), 13.33% (10/75) during spring and autumn, respectively; while no records were observed during winter season. The morphology of the recovered parasite was studied by using light and scanning electron microscopy. The adult worm characterized by anterior extremity with small mouth opening being surrounded by three lips provided with four sub-median cephalic papillae and one pair of lateral amphids. Body measurements showed that male worms were smaller than females measuring 1.22-2.43 (2.21 ± 0.1) mm in length and 0.21-0.34 (0.29 ± 0.01) mm in width. Females measured 1.9-3.7 (2.8 ± 0.1) mm in length and 0.24-0.42 (0.38 ± 0.01) mm in width. Comparing the present parasite with other species of the same genus described previously, several similarities were observed. However, peculiar new characteristics such as the arrangement of plectanes and somatic papillae, the presence of gubernaculum, the position of nerve ring, excretory pore, and vulval opening make it reasonable belongs to the family Cosmocercidae and identified as Cosmocerca sp. In addition, the present study was the first report for occurrence of cosmocercid species from the Mascarene grass frog in Egypt.

  16. Peculiarities of the formation of lettuce (Lactuca sativa L. varieties collection with reference characteristics

    Directory of Open Access Journals (Sweden)

    Н. В. Лещук

    2014-12-01

    Full Text Available Peculiarities of the formation of the collection of lettuce (Lactuca sativa L. varieties with reference characteristics are considered. Methodological requirements for the formation, grouping, maintenance, use and updating of the examples varieties collection for identifi cation of all lettuce varieties were scientifi cally grounded. Varieties with relevant morphological characteristics and notes of their expressions for vegetative and generative organs of lettuce plants were identifi ed. The use of formed examples varieties collection for the table of characteristics in the Guidelines for the conduct of tests for distinctness, uniformity and stability for lettuce (Lactuca sativa L. varieties was confi rmed.

  17. Potential protective effects of polysaccharide extracted from Ulva lactuca against male reprotoxicity induced by thiacloprid.

    Science.gov (United States)

    Kammoun, Intissar; Bkhairia, Intidhar; Ben Abdallah, Fatma; Jaballi, Imen; Ktari, Naourez; Boudawara, Ons; Nasri, Moncef; Gharsallah, Neji; Hakim, Ahmed; Ben Amara, Ibtissem

    2017-12-01

    Polysaccharides (PSs) from seaweeds have been reported to possess biological activity of potential medicinal values. The current study was conducted to establish the protective effects of PS extracted from Ulva lactuca against oxidative stress induced by Thiacloprid (THC) in the rat reproductive system. Rats were exposed either to THC, THC + PS (100 mg/kg), or THC + PS (200 mg/kg). Our study showed that THC induced severe disorders in the functional sperm parameters. A decrease in antioxidant activities and their genes expression were observed in the same group, compared to the controls. Our molecular data showing also a severe DNA breakdown in the testis of THC treated group. Moreover, THC treated group showed severe histopathological changes. Our results revealed that PS extracted from Ulva lactuca alleviated the THC induced reprotoxicity and reduced oxidative stress damages, DNA breakdown and histological injuries in the testis.

  18. [Analysis of the mineral elements of Lactuca sativa under the condition of different spectral components].

    Science.gov (United States)

    Chen, Xiao-Li; Guo, Wen-Zhong; Xue, Xu-Zhang; Wang, Li-Chun; Li, Liang; Chen, Fei

    2013-08-01

    Mineral elements absorption and content of Lactuca sativa under different spectral component conditions were studied by ICP-AES technology. The results showed that: (1) For Lactuca sativa, the average proportion for Ca : Mg : K : Na : P was 5.5 : 2.5 : 2.3 : 1.5 : 1.0, the average proportion for Fe : Mn : Zn : Cu : B was 25.9 : 5.9 : 2.8 : 1.1 : 1.0; (2) The absorptions for K, P, Ca, Mg and B are the largest under the LED treatment R/B = 1 : 2.75, red light from fluorescent lamps and LED can both promote the absorptions of Fe and Cu; (3)The LED treatments exhibiting relatively higher content of mineral elements are R/B = 1 : 2.75 and R/W = 1 : 1 while higher dry matter accumulations are R/B = 1 : 2.75 and B/W = 1 : 1.

  19. Production of acetone, butanol, and ethanol from biomass of the green seaweed Ulva lactuca.

    Science.gov (United States)

    van der Wal, Hetty; Sperber, Bram L H M; Houweling-Tan, Bwee; Bakker, Robert R C; Brandenburg, Willem; López-Contreras, Ana M

    2013-01-01

    Green seaweed Ulva lactuca harvested from the North Sea near Zeeland (The Netherlands) was characterized as feedstock for acetone, ethanol and ethanol fermentation. Solubilization of over 90% of sugars was achieved by hot-water treatment followed by hydrolysis using commercial cellulases. A hydrolysate was used for the production of acetone, butanol and ethanol (ABE) by Clostridium acetobutylicum and Clostridium beijerinckii. Hydrolysate-based media were fermentable without nutrient supplementation. C. beijerinckii utilized all sugars in the hydrolysate and produced ABE at high yields (0.35 g ABE/g sugar consumed), while C. acetobutylicum produced mostly organic acids (acetic and butyric acids). These results demonstrate the great potential of U. lactuca as feedstock for fermentation. Interestingly, in control cultures of C. beijerinckii on rhamnose and glucose, 1,2 propanediol was the main fermentation product (9.7 g/L). Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Carotenoids of Lettuce (Lactuca sativa L.) grown on soil enriched with spent coffee grounds

    OpenAIRE

    Cruz, Rebeca; Baptista, Paula; Cunha, Sara; Pereira, J.A.; Casal, Susana

    2012-01-01

    The impact of spent coffee grounds on carotenoid and chlorophyll content in lettuce (Lactuca sativa L. var. capitata) was evaluated. A greenhouse pot experiment was conducted with spent coffee amounts ranging from 0% to 20% (v/v). All evaluated pigments increased proportionally to spent coffee amounts. Lutein and β-carotene levels increased up to 90% and 72%, respectively, while chlorophylls increased up to 61%. Biomass was also improved in the presence of 2.5% to 10% spent coffee, decreasing...

  1. Peculiarities of the formation of lettuce (Lactuca sativa L.) varieties collection with reference characteristics

    OpenAIRE

    Н. В. Лещук

    2014-01-01

    Peculiarities of the formation of the collection of lettuce (Lactuca sativa L.) varieties with reference characteristics are considered. Methodological requirements for the formation, grouping, maintenance, use and updating of the examples varieties collection for identifi cation of all lettuce varieties were scientifi cally grounded. Varieties with relevant morphological characteristics and notes of their expressions for vegetative and generative organs of lettuce plants were identifi ed. Th...

  2. In vitro exposure of Ulva lactuca Linnaeus (Chlorophyta) to gasoline - Biochemical and morphological alterations.

    Science.gov (United States)

    Pilatti, Fernanda Kokowicz; Ramlov, Fernanda; Schmidt, Eder Carlos; Kreusch, Marianne; Pereira, Débora Tomazi; Costa, Christopher; de Oliveira, Eva Regina; Bauer, Cláudia M; Rocha, Miguel; Bouzon, Zenilda Laurita; Maraschin, Marcelo

    2016-08-01

    Refined fuels have considerable share of pollution of marine ecosystems. Gasoline is one of the most consumed fuel worldwide, but its effects on marine benthic primary producers are poorly investigated. In this study, Ulva lactuca was chosen as a biological model due to its cosmopolitan nature and tolerance to high levels and wide range of xenobiotics and our goal was to evaluate the effects of gasoline on ultrastructure and metabolism of that seaweed. The experimental design consisted of in vitro exposure of U. lactuca to four concentrations of gasoline (0.001%, 0.01%, 0.1%, and 1.0%, v/v) over 30 min, 1 h, 12 h, and 24 h, followed by cytochemical, SEM, and biochemical analysis. Increase in the number of cytoplasmic granules, loss of cell turgor, cytoplasmic shrinkage, and alterations in the mucilage were some of the ultrastructural alterations observed in thalli exposed to gasoline. Decrease in carotenoid and polyphenol contents, as well as increase of soluble sugars and starch contents were associated with the time of exposure to the xenobiotic. In combination, the results revealed important morphological and biochemical alterations in the phenotype of U. lactuca upon acute exposure to gasoline. This seaweed contain certain metabolites assigned as candidates to biomarkers of the environmental stress investigated and it is thought to be a promise species for usage in coastal ecosystems perturbation monitoring system. In addition, the findings suggest that U. lactuca is able to metabolize gasoline hydrocarbons and use them as energy source, acting as bioremediator of marine waters contaminated by petroleum derivatives. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Toxicity of tire wear particle leachate to the marine macroalga, Ulva lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Andrew, E-mail: aturner@plymouth.ac.u [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Rice, Lynsey [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2010-12-15

    Tire wear particles filed from the treads of end-of-life vehicle tires have been added to sea water to examine the release of Zn and the toxicity of the resulting leachate and dilutions thereof to the marine macroalga, Ulva lactuca. Zinc release appeared to be diffusion-controlled, with a conditional rate constant of 5.4 {mu}g[L(h){sup 1/2}]{sup -1}, and about 1.6% of total Zn was released after 120 h incubation. Exposure to increasing concentrations of leachate resulted in a non-linear reduction in the efficiency of photochemical energy conversion of U. lactuca and, with the exception of the undiluted leachate, increasing accumulation of Zn. Phototoxicity was significantly lower on exposure to equivalent concentrations of Zn added as Zn(NO{sub 3}){sub 2}, suggesting that organic components of leachate are largely responsible for the overall toxicity to the alga. Given the ubiquity and abundance of TWP in urban coastal sediments, the generation, biogeochemistry and toxicity of tire leachate in the marine setting merit further attention. - Tire wear leachate is toxic to Ulva lactuca and zinc is a potential bioindicator of leachate contamination in urban marine systems.

  4. Effects of Lactuca sativa extract on exploratory behavior pattern, locomotor activity and anxiety in mice

    Directory of Open Access Journals (Sweden)

    S.N. Harsha

    2012-05-01

    Full Text Available Objective: To evaluate antianxiety property of Lactuca sativa, an important and commonly used leafy vegetable known for its medicinal properties belongs to Asteraceae family. Methods: Elevated plus maze (EPM, open field test (OFT, rat exposure test, hyponeophagia and marble burying test were performed in mice models to assess the exploratory behaviour and to assess anxiolytic property of hydro-alcohol extract of Lactuca sativa. Diazepam (1 mg/kg body wt. served as the standard anxiolytic agent for all the tests. The dried extract of the plant leaf in doses of 100, 200 and 400 mg/kg body weight was administered orally to mice for duration of 15 or 30 days and evaluated exploratory behaviour, locomotor and anxiolytic activities. Results: Time spent and number of entries into the open arm was measured in EPM followed by total locomotor activity in OFT and latency to enter the food zone in hyponeophagia. Conclusions: The study suggested that hydro-alcohol extract of Lactuca sativa leaves possess potent anxiolytic property.

  5. Metabolic regulatory oscillations in intertidal green seaweed Ulva lactuca against tidal cycles.

    Science.gov (United States)

    Gupta, Vishal; Kushwaha, Hemant R

    2017-11-27

    The survival of wetland plant species largely relies on physiological adaptations essential for submergence and desiccation. Intertidal seaweeds, unlike terrestrial plants, have unique adaptations to submergence and can also sustain desiccation arising from tidal rhythms. This study determined the differential metabolic regulations in the inter-tidal seaweed species Ulva lactuca against the submergence and desiccation. During desiccation, the relative water content of the algal thalli declined with concomitant increase in reactive oxygen species (ROS) and lipid peroxidation. Nevertheless, the trends reversed during recovery on re-submergence and attained homeostasis. Metabolite profiling of U. lactuca revealed desiccation induced balance in energy reserve utilization by adjusting carbohydrate metabolism and switch over to ammonia metabolism. Upon re-submergence, thalli showed an increase in fermentative metabolites, pyruvate-alanine conversion, and the GABA shunt. Prolonged submergence induced substrate level phosphorylation mediated sugar biosynthesis while continuing the alternative carbon flux through fermentative metabolism, an increase in osmoprotectants glycine and betaine, sulfur bearing compounds cysteine and hypotaurine, and phenolic compound coniferaldehyde. The determined metabolic regulations in U. lactuca for submergence tolerance provide insights into potential evolutionarily conserved protective mechanisms across the green lineage and also highlights the possible role of sulfur oxoforms as strong free radical scavengers.

  6. Performance and feeding behaviour of two biotypes of the black currant-lettuce aphid, Nasonovia ribisnigri, on resistant and susceptible Lactuca sativa near-isogenic lines

    NARCIS (Netherlands)

    Broeke, ten C.J.M.; Dicke, M.; Loon, van J.J.A.

    2013-01-01

    The black currant-lettuce aphid, Nasonovia ribisnigri, is an important pest of cultivated lettuce, Lactuca sativa. Since 1982, the control of this aphid on lettuce is largely based on host plant resistance, conferred by the Nr gene, introgressed from Lactuca virosa. The resistance mechanism remains

  7. The Newly Isolated Endophytic Fungus Paraconiothyrium sp. LK1 Produces Ascotoxin

    Directory of Open Access Journals (Sweden)

    Sang-Mo Kang

    2012-01-01

    Full Text Available We have isolated five endophytic fungi from the roots of Capsicum annuum, Cucumis sativus and Glycine max. The culture filtrates (CF of these endophytes were screened on dwarf mutant rice (Waito-C and normal rice (Dongjin-byeo. Endophyte CAC-1A significantly inhibited the growth of Waito-C and Dongjin-byeo. Endophyte CAC-1A was identified as Paraconiothyrium sp. by sequencing the ITS rDNA region and phylogenetic analysis. The ethyl acetate fraction of Paraconiothyrium sp. suppressed the germination of Lactuca sativa and Echinochloa crus-galli seeds. The ethyl acetate fraction of the endophyte was subjected to bioassay-guided isolation and we obtained the phytotoxic compound ascotoxin (1 which was characterized through NMR and GC/MS techniques. Ascotoxin revealed 100% inhibitory effects on seed germination of Echinochloa crus-galli. Compound (1 was isolated for the first time from Paraconiothyrium sp.

  8. Effect of Hydroalcoholic Extract of Lactuca Serriola on Blood Glucose in Streptozotocin (STZ- Induced Diabetic the Rats

    Directory of Open Access Journals (Sweden)

    F Mohamad janni

    2016-05-01

    Full Text Available Introduction: Diabetes mellitus (DM is a disorder caused by abnormal insulin secretion and is diagnosed by the presence of hyperglycemia. Insulin is one of the drugs used by diabetics patients .This drug also like other drugs has side effects, but in this way using herbal medicine is more effective. This study is to determine the effect of hydroalcoholic extract of Lactuca serriola on blood glucose in Streptozotocin (STZ- induced diabetic male rats. Methods: In study of 30 rats with an average weight of 200-230 g were divided into 5 groups consisted of 6 rats in each group comprised control, diabetic control and 3 groups treated orally with extract of Lactuca serriola. Diabetes was induced by STZ injection (IP at a dose of 50mg/kg. The doses of 250,350 and 450 mg/kg of extract were injected intraperitoneally during 6 weeks (40 days. The data were analyzed by one way variance analysis and Tukey’s test using SPSS Version 17 (p<0.05. Results: This research showed that the dosage of 250 mg/kg of extract of Lactuca serriola had less effect on blood sugar, and the dosage of 450 mg/kg of Lactuca serriola had a greater influence on blood sugar levels at different days, but dosage of 350 mg/kg  and dose of 450 mg/kg only could more significantly decrease the level of blood sugar. Conclusion: According the results of the study, the hydroalcolic extract of Lactuca serriola had the hypoglycemic effects on diabetic male rats  and it can be helpful for drug production in the control of Lactuca serriola. This drug consists of natural and synthetic substances: flavonoid, Alkaloid and Gamma-Aminobutyric Acid.

  9. The effect of soil environment on germination and emergence of prickly lettuce (Lactuca serriola L.

    Directory of Open Access Journals (Sweden)

    Jan Kapeluszny

    2012-12-01

    Full Text Available In 2007 mature achenes of prickly lettuce (Lactuca serriola L. were collected from a winter wheat crop growing on loess-derived brown earth soil, from the side of a dirt road, and from a hybrid alfalfa crop growing on heavy rendzina soil. In March 2008 the germination ability of achenes and the length of roots and above-ground parts of L. serriola seedlings were determined. The experiment was set up as a completely randomized design in 6 replicates and it was done in dishes. The dishes were filled with loess-derived brown soil and podzolic soil derived from light loamy sand with different pH values of 4.5, 5.5 and 7.0 obtained using laboratory methods. The second experiment evaluated the effect of medium type and light conditions on the germination of Lactuca serriola achenes. The experimental design was the same as in the above described experiment. The study found that there were significantly more germinating seeds from the plants growing in the alfalfa crop and on the dirt roadside compared to the plants from the wheat crop. Emerging plants showed higher germination ability on loess-derived soil with a pH of 5.5 and 7.0 than on podzolic soil derived from sand with the same pH. Lactuca serriola prefers soils rich in calcium compounds, and developing segetal cenopopulations produce diaspores capable of germination, thereby the numbers of individuals can increase and the continuity of this species in crop fields can be maintained. Seeds germinated significantly better in the dark than under the conditions of 12-hour illumination.

  10. Sterol composition of the Adriatic Sea algae Ulva lactuca, Codium dichotomum, Cystoseira adriatica and Fucus virsoides

    Directory of Open Access Journals (Sweden)

    RADOMIR KAPETANOVIC

    2005-12-01

    Full Text Available The sterol composition of two green algae and two brown algae from the South Adriatic was determined. In the green alga Ulva lactuca, the principal sterols were cholesterol and isofucosterol. In the brown alga Cystoseira adriatica, the main sterols were cholesterol and stigmast-5-en-3ß-ol, while the characteristic sterol of the brown algae, fucosterol, was found only in low concentration. The sterol fractions of the green alga Codium dichotomum and the brown alga Fucus virsoides contained practically only one sterol each, comprising more than 90 % of the total sterols (clerosterol in the former and fucosterol in the latter.

  11. Effects of kaurane diterpene derivatives on germination and growth of Lactuca sativa seedlings.

    Science.gov (United States)

    Vieira, Henriete S; Takahashi, Jacqueline A; Pimenta, Lúcia P S; Boaventura, Maria Amélia D

    2005-01-01

    Kaurenoic and grandiflorenic acid, isolated from Wedelia paludosa (Asteraceae), some derivatives from these acids (alcohols, esters, amides, lactones, oximes) and other naturally occurring kaurane diterpenes were tested for their action on the growth of radical and shoot of Lactuca sativa. Gibberellic acid, GA3, a commercially available phytohormone, belonging to the same class of diterpenes, was also tested. Some of the tested substances showed a remarkable activity either in the inhibition or in stimulation of L. sativa growth. The activity, in some cases, was even higher than that of GA3.

  12. Toxicity Effect of Cr Stress on Seed Germination and Seedling Growth in Lactuca Sativa

    Science.gov (United States)

    Ma, Wan Zheng; Ma, Wan Min; Du, Ying Ying; Dan, Qiong Peng; Yin, Bing; Dai, Shan Shan; Hao, Xiang

    2018-03-01

    The impact of Cr6+ on the growth of lactuca sativa in Greenhouse Cucumber was investigated. The seeds of lacuna sativa Italian bolting resistance lettuce were treated by different Cr6+ concentration to study the effects on its seed germination and seedling growth. The results showed that the seed germination rate, vigor index of seedlings decreased with increment of Cr6+ concentration to varying degrees, and vigor germination, vigor index, raw weight, root length significantly lower. The absorption of lettuce seedlings on different nutrient elements is impacted by the concentration of Cr6+.

  13. Blue and Green Light-Induced Phototropism in Arabidopsis thaliana and Lactuca sativa L. Seedlings 1

    Science.gov (United States)

    Steinitz, Benjamin; Ren, Zhangling; Poff, Kenneth L.

    1985-01-01

    Exposure time-response curves for blue and green light-induced phototropic bending in hypocotyls of Arabidopsis thaliana (L.) Heynh. and Lactuca sativa L. seedlings are presented. These seedlings show significant phototropic sensitivity up to 540 to 550 nanometers. Since wave-lengths longer than 560 nanometers do not induce phototropic bending, it is suggested that the response to 510 to 550 nanometers light is mediated by the specific blue light photoreceptor of phototropism. We advise care in the use of green `safelights' for studies of phototropism. PMID:16664021

  14. Foliar exposure of the crop Lactuca sativa to silver nanoparticles: Evidence for internalization and changes in Ag speciation

    Energy Technology Data Exchange (ETDEWEB)

    Larue, Camille, E-mail: camille.larue@rub.de [ISTerre, Université Grenoble 1, CNRS, F-38041 Grenoble (France); Castillo-Michel, Hiram, E-mail: castillo@esrf.fr [ESRF, Beamline ID21, Grenoble (France); Sobanska, Sophie, E-mail: sophie.sobanska@univ-lille1.fr [LASIR, UMR CNRS 8516, Université Lille 1, Bât C5, 59655 Villeneuve d’Ascq Cedex (France); Cécillon, Lauric, E-mail: lauric.cecillon@irstea.fr [ISTerre, Université Grenoble 1, CNRS, F-38041 Grenoble (France); Bureau, Sarah, E-mail: sarah.bureau@ujf-grenoble.fr [ISTerre, Université Grenoble 1, CNRS, F-38041 Grenoble (France); Barthès, Véronique, E-mail: veronique.barthes@cea.fr [CEA/LITEN/DTNM/L2T, CEA Grenoble, 38054 Grenoble Cedex 9 (France); Ouerdane, Laurent, E-mail: laurent.ouerdane@univ-pau.fr [LCABIE/IPREM-UMR 5254, Université de Pau et des Pays de l‘Adour, 64053 Pau Cedex 9 (France); Carrière, Marie, E-mail: marie.carriere@cea.fr [UMR E3 CEA-UJF/LAN, 38054 Grenoble Cedex 9 (France); Sarret, Géraldine, E-mail: geraldine.sarret@ujf-grenoble.fr [ISTerre, Université Grenoble 1, CNRS, F-38041 Grenoble (France)

    2014-01-15

    Highlights: • Ag-NPs are internalized inside lettuce leaves after foliar exposure to a suspension of Ag-NPs. • A classical washing process is inefficient at decreasing significantly Ag content. • Ag-NPs in plants undergo oxidation, and resulting ionic Ag are complexed with organic compounds including thiol-containing molecules. • Foliar exposure to Ag-NPs does not lead to detectable phytotoxicity symptoms. -- Abstract: The impact of engineered nanomaterials on plants, which act as a major point of entry of contaminants into trophic chains, is little documented. The foliar pathway is even less known than the soil-root pathway. However, significant inputs of nanoparticles (NPs) on plant foliage may be expected due to deposition of atmospheric particles or application of NP-containing pesticides. The uptake of Ag-NPs in the crop species Lactuca sativa after foliar exposure and their possible biotransformation and phytotoxic effects were studied. In addition to chemical analyses and ecotoxicological tests, micro X-ray fluorescence, micro X-ray absorption spectroscopy, time of flight secondary ion mass spectrometry and electron microscopy were used to localize and determine the speciation of Ag at sub-micrometer resolution. Although no sign of phytotoxicity was observed, Ag was effectively trapped on lettuce leaves and a thorough washing did not decrease Ag content significantly. We provide first evidence for the entrapment of Ag-NPs by the cuticle and penetration in the leaf tissue through stomata, for the diffusion of Ag in leaf tissues, and oxidation of Ag-NPs and complexation of Ag{sup +} by thiol-containing molecules. Such type of information is crucial for better assessing the risk associated to Ag-NP containing products.

  15. Monitoramento de raças de Bremia lactucae em 2010 e 2011 no Estado de São Paulo Monitoring of Bremia lactucae races in 2010 and 2011 in the state of São Paulo

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    Francine de Souza Galatti

    2012-12-01

    Full Text Available A alface é uma das mais importantes hortaliças folhosas cultivadas no Brasil. Porém, com a intensificação da produção, a dificuldade em se cultivar essa hortaliça tem aumentado principalmente pela infestação das áreas de produção pelo fitopatógeno Bremia lactucae Regel, agente causador do míldio, uma das principais doenças da alface. O objetivo deste trabalho foi identificar raças de Bremia lactucae nos anos de 2010 e 2011 nos principais municípios produtores de alface do Estado de São Paulo. Para isso, coletaram-se folhas com esporângios de B. lactucae em municípios produtores de alface, sendo que cada amostra foi considerada um isolado, totalizando 56 e 96 nos anos de 2010 e 2011, respectivamente. Os esporângios coletados foram multiplicados na cultivar suscetível Solaris, com posterior inoculação nas cultivares diferenciadoras, realizando-se as avaliações no mesmo dia do aparecimento da primeira esporulação na cultivar suscetível 'Green Tower' (DM 0. No ano de 2010, identificou-se um novo código de B. lactucae em alface (63/31/03/00, correspondente a uma nova raça na qual se propôs a denominação de SPBl:07. No ano de 2011, outros dois códigos de B. lactucae foram identificados (31/63/51/00 e 31/63/9/00, aos quais se propôs as denominações de SPBl:08 e SPBl:09, respectivamente.Lettuce is one of the most important leafy vegetables grown in Brazil. However, intensification of its production has led to increased difficulty in cultivating this vegetable, especially due to infestation of producing areas with the phytopathogen Bremia lactucae Regel, the causative agent of downy mildew, one of the worst diseases affecting lettuce. The aim of this study was to identify B. lactucae races in 2010 and 2011 in major lettuce producing cities in the state of Sao Paulo. Thus, leaves with sporangia of B. lactucae were collected from lettuce producing cities and each sample was considered an isolate, totaling 56 and 96 in

  16. Genetic Transformation and Hairy Root Induction Enhance the Antioxidant Potential of Lactuca serriola L.

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    Mohamed A. El-Esawi

    2017-01-01

    Full Text Available Lactuca serriola L. is a herbaceous species, used for human nutrition and medicinal purposes. The high antioxidant capacity of L. serriola indicates the possibility of enhancing its edible and health potential by increasing the flavonoid and phenolic contents. The present study aimed at enhancing the production of phenolics and flavonoids by hairy root cultures in Lactuca serriola transformed with Agrobacterium rhizogenes strain AR15834 harbouring the rolB gene. The genetic transformation of rolB in transformed roots was validated, and rolB expression level was evaluated using real-time qPCR analysis. Expression levels of flavonoid biosynthesis genes (CHI, PAL, FLS, and CHS were assessed in the hairy and nontransformed roots. Results showed higher expression levels in the transgenic roots than in the nontransformed ones (p<0.01. Transgenic hairy roots exhibited a 54.8–96.7% increase in the total phenolic content, 38.1–76.2% increase in the total flavonoid content, and 56.7–96.7% increase in the total reducing power when compared with the nontransgenic roots (p<0.01. DPPH results also revealed that the transgenic hairy roots exhibited a 31.6–50% increase in antioxidant potential, when compared to normal roots. This study addressed the enhancement of secondary metabolite biosynthesis by hairy root induction in L. serriola.

  17. Role of Ulva lactuca Extract in Alleviation of Salinity Stress on Wheat Seedlings

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    Wael M. Ibrahim

    2014-01-01

    Full Text Available Seaweeds are potentially excellent sources of highly bioactive materials that could represent useful leads in the alleviation of salinity stress. The effects of presoaking wheat grains in water extract of Ulva lactuca on growth, some enzymatic activities, and protein pattern of salinized plants were investigated in this study. Algal presoaking of grains demonstrated a highly significant enhancement in the percentage of seed germination and growth parameters. The activity of superoxide dismutase (SOD and catalase (CAT increased with increasing the algal extract concentration while activity of ascorbate peroxidase (APX and glutathione reductase (GR was decreased with increasing concentration of algal extract more than 1% (w/v. The protein pattern of wheat seedling showed 12 newly formed bands as result of algal extract treatments compared with control. The bioactive components in U. lactuca extract such as ascorbic acid, betaine, glutathione, and proline could potentially participate in the alleviation of salinity stress. Therefore, algal presoaking is proved to be an effective technique to improve the growth of wheat seedlings under salt stress conditions.

  18. Lead (Pb heavy metal impacts in the green Ulva lactuca (Chlorophyceae marine algae

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    B. Saleh

    2016-05-01

    Full Text Available Toxicity of different lead (Pb (0, 2, 4 and 8 mg/L concentrations in the green Ulva lactuca (Chlorophyta marine algae at physiological level has been investigated 48 h after Pb treatment under laboratory conditions. Thalus algae damages followed Pb treatment as revealed by microscopy test showed that the 4 and 8 mg/L Pb caused morphological changes in cells viability; whereas, no effect observed at the lowest Pb applied concentration (2 mg/L. Data revealed that Pb stress caused reduction in most investigated physiological parameters i.e. Pigments content, osmotic potential and membrane stability index values. This decline in osmotic potential was significantly (p ≤ 0.001 different. Whereas, estimated electric conductivity (EC values increased significantly (p ≤ 0.001 as applied Pb concentration increased. The current study allowed somewhat to highlight and better understanding Pb impacts in U. lactuca algae. Thereby, the studied algae could be used as a useful bioindicator in Pb polluted ecosystems.

  19. Detection of Genetic Variations in Marine Algae Ulva lactuca (Chlorophyta Induced by Heavy Metal Pollutants

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    Basel Saleh

    2015-09-01

    Full Text Available Ulva lactuca (Chlorophyta green macroalgae has been successfully used as bioindicator for heavy metals pollution in ecosystems. Random amplified microsatellite polymorphism (RAMP marker was employed to investigate genetic DNA pattern variability in green U. lactuca 5 days after exposure to Cu, Pb, Cd and Zn heavy metals stress. Genomic template stability (GTS% value was employed as a qualitative DNA changes measurement based on RAMP technique. In this respect, estimated GTS% value was recorded to be 65.215, 64.630, 59.835 and 59.250% for Pb, Cu, Cd and Zn treatment, respectively. Moreover, genetic similarity (GS induced by the above heavy metals was also evaluated to measure genetic distance between algae treated plants and their respective control. In this respect, estimated GS values generated by RAMP marker ranged between 0.576 (between control and Zn treatment - 0.969 (for both case; between Pb and Cu and between Cd and Zn treatment with an average of 0.842. Based upon data presented herein based on variant bands number (VB, GTS% and GS values; the present study could be suggested that Pb and Cu followed similar tendency at genomic DNA changes. Similar finding was also observed with Cd and Zn ions. Thereby, RAMP marker successfully highlighted DNA change patterns induced by heavy metals stress.

  20. Cold-induced imbibition damage of lettuce embryos: A study using cryo-scanning electron microscopy

    NARCIS (Netherlands)

    Nijsse, J.; Walther, P.; Hoekstra, F.

    2004-01-01

    The impact of rehydration on a multicellular organism was studied in lettuce (Lactuca sativa L.) embryos, using cryo-scanning electron microscopy (cryo-SEM). Naked embryos were sensitive to imbibitional stress, whereas embryos with an intact, thick-walled endosperm were not. Imbibitional injury to

  1. Distribution of genetic diversity in wild European populations of prickly lettuce (Lactuca serriola): implications for plant genetic resources management

    NARCIS (Netherlands)

    Wiel, van de C.C.M.; Sretenovic Rajicic, T.; Treuren, van R.; Dehmer, K.J.; Linden, van der C.G.; Hintum, van T.J.L.

    2010-01-01

    Genetic variation in Lactuca serriola, the closest wild relative of cultivated lettuce, was studied across Europe from the Czech Republic to the United Kingdom, using three molecular marker systems, simple sequence repeat (SSR, microsatellites), AFLP and nucleotide-binding site (NBS) profiling. The

  2. Evolution and genetic population structure of prickly lettuce (Lactuca serriola) and its RGC2 resistance gene cluster

    NARCIS (Netherlands)

    Kuang, H.; Eck, van H.J.; Sicard, D.; Michelmore, R.; Nevo, E.

    2008-01-01

    Genetic structure and diversity of natural populations of prickly lettuce (Lactuca serriola) were studied using AFLP markers and then compared with the diversity of the RGC2 disease resistance gene cluster. Screening of 696 accessions from 41 populations using 319 AFLP markers showed that eastern

  3. Acquisition and ecological characterization of Lactuca serriola L. germplasm collected in the Czech Republic, , Germany, the Netherlands and United Kingdom

    NARCIS (Netherlands)

    Lebeda, A.; Dolezalova, I.; Kristkova, E.; Dehmer, K.J.; Astley, D.; Wiel, van de C.C.M.; Treuren, van R.

    2007-01-01

    Expeditions were conducted in the Czech Republic, Germany, the Netherlands and United Kingdom in 2001 (partly 1998) to study Lactuca serriola L. (prickly lettuce, compass plant) geographic distribution, ecology, habitat characteristics and occurrence of diseases and pests on this species. During

  4. TOXICITY OF METHYL-TERT BYTYL ETHER (MTBE) TO PLANTS (AVENA SATIVA, ZEA MAYS, TRITICUM AESTIVUM, AND LACTUCA SATIVA)

    Science.gov (United States)

    Effects of Methyl tert-butyl ether (MTBE) on the germination of seeds and growth of the plant were studied in some laboratory experiments. Test plants were wild oat (Avena sative), sweet corn (Zea mays), wheat (Triticum aestivum), and lettuce (Lactuca sativa). Seed germination,...

  5. Occupational dermatitis from Lactuca sativa (lettuce) and Cichorium (endive). Simultaneous occurrence of immediate and delayed allergy as a cause of contact dermatitis.

    Science.gov (United States)

    Krook, G

    1977-02-01

    Four patients with occupational contact dermatitis to Lactuca sativa had cross-sensitivity to Cichorium endivia. One of the patients also had contact urticaria to Lactuca and Cichorium, and another reacted positively to scratch tests with these plants as a sign of immediate allergy. In two cases such immediate allergy was considered the cause of a vesicular, intense itching eruption within a few minutes of contact with fresh leaves of Lactuca on previously eczematous skin. The severe chronic dermatitis of the hands of these patients is ascribed to combined delayed and immediate allergy.

  6. SP. Pescado

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    Renato Gendre

    2003-12-01

    Full Text Available Nell'occhiello di un articolo dal titolo Il Peru dei de[Jini rosa e de/la grande pioggia si legge: "da una partenza  in aereo al «pescado»  che ti  sfamera."1 Questa parola spagnola, giustamente chiusa tra caporali, a noi pare molto interes­ sante, perche, nonostante l'apparenza, non ha nulla da spartire sotto i1 profilo se­ mantico con l'it. pescato. lnfatti, tutti i piu importanti dizionari della lingua italiana, di ieri e di oggi, etimologici e non 2, registrano  accanto a pescata,  ii lemma pescato, 3 ma lo spiegano come "quantita di pesce catturato nel corso di una battuta o di una stagione di pesca",4 mentre lo sp. pescado  indica i1 "pesce (solo nel senso di: pesGe pescato da mangiare [...]".s

  7. Diversity in photosynthetic electron transport under [CO2]-limitation: the cyanobacterium Synechococcus sp. PCC 7002 and green alga Chlamydomonas reinhardtii drive an O2-dependent alternative electron flow and non-photochemical quenching of chlorophyll fluorescence during CO2-limited photosynthesis.

    Science.gov (United States)

    Shimakawa, Ginga; Akimoto, Seiji; Ueno, Yoshifumi; Wada, Ayumi; Shaku, Keiichiro; Takahashi, Yuichiro; Miyake, Chikahiro

    2016-12-01

    Some cyanobacteria, but not all, experience an induction of alternative electron flow (AEF) during CO 2 -limited photosynthesis. For example, Synechocystis sp. PCC 6803 (S. 6803) exhibits AEF, but Synechococcus elongatus sp. PCC 7942 does not. This difference is due to the presence of flavodiiron 2 and 4 proteins (FLV2/4) in S. 6803, which catalyze electron donation to O 2 . In this study, we observed a low-[CO 2 ] induced AEF in the marine cyanobacterium Synechococcus sp. PCC 7002 that lacks FLV2/4. The AEF shows high affinity for O 2 , compared with AEF mediated by FLV2/4 in S. 6803, and can proceed under extreme low [O 2 ] (about a few µM O 2 ). Further, the transition from CO 2 -saturated to CO 2 -limited photosynthesis leads a preferential excitation of PSI to PSII and increased non-photochemical quenching of chlorophyll fluorescence. We found that the model green alga Chlamydomonas reinhardtii also has an O 2 -dependent AEF showing the same affinity for O 2 as that in S. 7002. These data represent the diverse molecular mechanisms to drive AEF in cyanobacteria and green algae. In this paper, we further discuss the diversity, the evolution, and the physiological function of strategy to CO 2 -limitation in cyanobacterial and green algal photosynthesis.

  8. Nutrient uptake efficiency of Gracilaria chilensis and Ulva lactuca in an IMTA system with the red abalone Haliotis rufescens

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    Juan Macchiavello

    2014-07-01

    Full Text Available The current study examined the nutrient uptake efficiency of Ulva lactuca and Gracilaria chilensis cultivated in tanks associated with the wastewater of a land-based abalone culture. The experiments evaluated different seaweed stocking densities (1200, 1900, 2600, and 3200 g m-2 and water exchange rates (60, 80, 125, and 250 L h-1. The results show that both U. lactuca and G. chilensis were efficient in capturing and removing all of the inorganic nutrients originating from the abalone cultivation for all of the tested conditions. Furthermore, an annual experiment was performed with U. lactuca, cultivated at a stocking density of 1900 g m-2 and at a water exchanged rate of 125 L h-1, in order to evaluate seasonal changes in the nutrient uptake efficiency, productivity, and growth rate associated with the wastewater of a land-based abalone culture. The results confirmed high uptake efficiency during the entire year, equivalent to a 100% removal of the NH4, NO3, and PO4 produced by the land-based abalone culture. The growth rate and productivity of U. lactuca presented a marked seasonality, increasing from fall until summer and varying from 0.5 ± 0.2% to 2.6 ± 0.2% d-1 and 10 ± 6.1% to 73.6 ± 8.4% g m-2 d-1 for sustainable growth rate and productivity, respectively. We conclude that there is sufficient evidence that demonstrates the high possibility of changing the traditional monoculture system of abalone in Chile, to a sustainable integrated multi-trophic aquaculture system, generating positive environmental externalities, including the use of U. lactuca as a biofiltration unit.

  9. Enteroparasitas em alfaces (Lactuca sativa comercializadas na cidade de Guarapuava (PR / Enteroparasites on commercial lettuce (Lactuca sativa in Guarapuava City, Paraná State

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    Silvia Cristina Osaki

    2010-08-01

    Full Text Available O consumo de hortaliças cruas constitui importante meio de transmissão de enteroparasitoses. O objetivo deste trabalho foi avaliar a contaminação parasitária em alfaces (Lactuca sativa comercializadas na cidade de Guarapuava (PR. No período de julho/2005 a junho/2006, 52 supermercados foram visitados, com colheita de um pé de alface. A análise parasitológica foi realizada após duas lavagens, filtragem em gaze e sedimentação. O sedimento, corado pelo lugol, foi analisado microscopicamente por exame direto e após centrífugo-flutuação em sulfato de zinco. Das 52 amostras de alface avaliadas, 18 (34,6% apresentaram uma ou mais estruturas parasitárias como cistos de Giardia spp. (7,7%, de Entamoeba spp. (11,5% e de Balantidium coli (3,8%, oocistos de coccídios (7,7% e ovos de Capillaria spp. (3,8%. Esse alto número de amostras contaminadas aponta deficiências na cadeia produtiva dessas hortaliças, indicando a necessidade de adequada higienização antes de seu consumo. AbstractThe ingestion of raw vegetables is an important mode of enteroparasites transmission. The aim of this study was to evaluate the parasitological contamination of lettuce (Lactuca sativa commercialized in Guarapuava City, Parana State. Fifty-two samples of lettuce were collected from supermarkets during the period of July 2005 and June 2006. Parasitological analysis was realized by the sedimentation technique. Lugol-stained sediments were microscopically analyzed by direct exam and after centrifugation-fluctuation in zinc sulfate. A total of 18 out of 52 lettuce samples analyzed (34.6% were positive for one or more parasitic structures. The parasites found in the analysis were Giardia spp. (7.7%, Entamoeba spp. (11.5%, Balantidium coli (3.8%, coccidian oocysts (7.7% and Capillaria spp. eggs (3.8%. Such high occurrence of contaminated samples revealed deficiencies in the chain of lettuce cultivation, which suggests a need for improvement in the current

  10. Spin-polarized semiconductors: tuning the electronic structure of graphene by introducing a regular pattern of sp3 carbons on the graphene plane.

    Science.gov (United States)

    Jing, Long; Huang, Ping; Zhu, Huarui; Gao, Xueyun

    2013-01-28

    First-principles calculations (generalized gradient approximation, density functional therory (DFT) with dispersion corrections, and DFT plus local atomic potential) are carried out on the stability and electronic structures of superlattice configurations of nitrophenyl diazonium functionalized graphene with different coverage. In the calculations, the stabilities of these structures are strengthened significantly since van der Waals interactions between nitrophenyl groups are taken into account. Furthermore, spin-polarized and wider-bandgap electronic structures are obtained when the nitrophenyl groups break the sublattice symmetry of the graphene. The unpaired quasi-localized p electrons are responsible for this itinerant magnetism. The results provide a novel approach to tune graphene's electronic structures as well as to form ferromagnetic semiconductive graphene. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Phyotoxicity of diesel soil contamination on the germination of Lactuca sativa and Ipomoea batatas.

    Science.gov (United States)

    Fatokun, Kayode; Lewu, Francis Bayo; Zharare, Godfrey Elijah

    2015-11-01

    Phytotoxic effect of diesel contaminated soil on germination rate of Lactuca sativa and Ipomoea batatas, at two concentrations ranges (0-6ml and 0-30ml), were investigated and compared. Diesel soil contamination was simulated and soil samples were taken from contaminated soil at 1, 5,10, 15, 25, 50, 75 and 100 days should be after planting. The result showed that in both plant species, diesel inhibited germination in a concentration dependent manner, Also, the influence of diesel contamination diminished with increased time duration; suggesting possible reduction in diesel toxicity over time. However, germination of lettuce was significant and negatively correlated (r2 = -0.941) with diesel contamination as compared to sweet potato (r2 = -0.638).Critical concentration of diesel in relation to seed germination of L. sativa was lower than vegetative germination of I. batatas, indicating that germination of I. batatas was less sensitive to diesel contamination as compared to L. sativa.

  12. Inhibitory effect of marine green algal extracts on germination of Lactuca sativa seeds.

    Science.gov (United States)

    Choi, Jae-Suk; Choi, In Soon

    2016-03-01

    The allelopathic potential of nine green seaweed species was examined based on germination and seedling growth of lettuce (Lactuca sativa L.). Out of nine methanol extracts, Capsosiphon fulvescens and Monostroma nitidum extracts completely inhibited germination of L. sativa at 4 mg/filter paper after 24 hr of treatment. Water extracts of these seaweeds generally showed low anti-germination activities than methanol extracts. Of the nine water extracts, Enteromorpha linza extract completely inhibited L. sativa germination at 16 mg/filter paper after 24 hrs. To identify the primary active compounds, C. fulvescens. powder was successively fractionated according to polarity, and the main active agents against L. sativa were determined to be lipids (0.0% germination at 0.5 mg of lipids/paper disc). According to these results, extracts of C. fulvescens can be used to develop natural herbicidal agents and manage terrestrial weeds.

  13. Transfer and expression of the rabbit defensin NP-1 gene in lettuce (Lactuca sativa).

    Science.gov (United States)

    Song, D; Xiong, X; Tu, W F; Yao, W; Liang, H W; Chen, F J; He, Z Q

    2017-01-23

    Lettuce (Lactuca sativa L.) is an annual plant of the daisy family, Asteraceae, with high food and medicinal value. However, the crop is susceptible to several viruses that are transmitted by aphids and is highly vulnerable to post-harvest diseases, as well as insect and mammal pests and fungal and bacterial diseases. Here, the rabbit defensin gene NP-1 was transferred into lettuce by Agrobacterium-mediated transformation to obtain a broad-spectrum disease-resistant lettuce. Transgenic lettuce plants were selected and regenerated on selective media. The presence of the NP-1 gene in these plants was confirmed by western blot analyses. Resistance tests revealed native defensin NP-1 expression conferred partial resistance to Bacillus subtilis and Pseudomonas aeruginosa, which suggests new possibilities for lettuce disease resistance.

  14. Specific in planta recognition of two GKLR proteins of the downy mildew Bremia lactucae revealed in a large effector screen in lettuce.

    Science.gov (United States)

    Stassen, Joost H M; den Boer, Erik; Vergeer, Pim W J; Andel, Annemiek; Ellendorff, Ursula; Pelgrom, Koen; Pel, Mathieu; Schut, Johan; Zonneveld, Olaf; Jeuken, Marieke J W; Van den Ackerveken, Guido

    2013-11-01

    Breeding lettuce (Lactuca sativa) for resistance to the downy mildew pathogen Bremia lactucae is mainly achieved by introgression of dominant downy mildew resistance (Dm) genes. New Bremia races quickly render Dm genes ineffective, possibly by mutation of recognized host-translocated effectors or by suppression of effector-triggered immunity. We have previously identified 34 potential RXLR(-like) effector proteins of B. lactucae that were here tested for specific recognition within a collection of 129 B. lactucae-resistant Lactuca lines. Two effectors triggered a hypersensitive response: BLG01 in 52 lines, predominantly L. saligna, and BLG03 in two L. sativa lines containing Dm2 resistance. The N-terminal sequences of BLG01 and BLG03, containing the signal peptide and GKLR variant of the RXLR translocation motif, are not required for in planta recognition but function in effector delivery. The locus responsible for BLG01 recognition maps to the bottom of lettuce chromosome 9, whereas recognition of BLG03 maps in the RGC2 cluster on chromosome 2. Lactuca lines that recognize the BLG effectors are not resistant to Bremia isolate Bl:24 that expresses both BLG genes, suggesting that Bl:24 can suppress the triggered immune responses. In contrast, lettuce segregants displaying Dm2-mediated resistance to Bremia isolate Bl:5 are responsive to BLG03, suggesting that BLG03 is a candidate Avr2 protein.

  15. Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L. cultivars and mapping genes

    Directory of Open Access Journals (Sweden)

    Rauscher Gilda

    2013-01-01

    Full Text Available Abstract Background Lettuce (Lactuca sativa L. is the major crop from the group of leafy vegetables. Several types of molecular markers were developed that are effectively used in lettuce breeding and genetic studies. However only a very limited number of microsattelite-based markers are publicly available. We have employed the method of enriched microsatellite libraries to develop 97 genomic SSR markers. Results Testing of newly developed markers on a set of 36 Lactuca accession (33 L. sativa, and one of each L. serriola L., L. saligna L., and L. virosa L. revealed that both the genetic heterozygosity (UHe = 0.56 and the number of loci per SSR (Na = 5.50 are significantly higher for genomic SSR markers than for previously developed EST-based SSR markers (UHe = 0.32, Na = 3.56. Fifty-four genomic SSR markers were placed on the molecular linkage map of lettuce. Distribution of markers in the genome appeared to be random, with the exception of possible cluster on linkage group 6. Any combination of 32 genomic SSRs was able to distinguish genotypes of all 36 accessions. Fourteen of newly developed SSR markers originate from fragments with high sequence similarity to resistance gene candidates (RGCs and RGC pseudogenes. Analysis of molecular variance (AMOVA of L. sativa accessions showed that approximately 3% of genetic diversity was within accessions, 79% among accessions, and 18% among horticultural types. Conclusions The newly developed genomic SSR markers were added to the pool of previously developed EST-SSRs markers. These two types of SSR-based markers provide useful tools for lettuce cultivar fingerprinting, development of integrated molecular linkage maps, and mapping of genes.

  16. Pharmacological Effects of Lactuca serriola L. in Experimental Model of Gastrointestinal, Respiratory, and Vascular Ailments

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    Khalid Hussain Janbaz

    2013-01-01

    Full Text Available Lactuca serriola L. has traditionally been used in folkloric medicine to manage respiratory, gastrointestinal, and multiple other ailments. The present study was undertaken to explore the effect of methanol extract of L. serriola on isolated rabbit tissue preparations, that is, jejunum, trachea, and aorta in an attempt to validate its folkloric use in traditional medicine for gastrointestinal, respiratory, and vascular ailments. The application of the methanol extract to isolated rabbit jejunum preparations exhibited concentration-dependent spasmogenic effect (0.03 to 3.0 mg/mL, but interestingly further increase in concentration (5.0 mg/mL resulted in complete spasmolytic effect. The pretreatment of the tissue preparations with atropine (0.1 μM caused the suppression of the contractile response. Moreover, the same extract also caused relaxation of K+-(80 mM induced spastic contractions of isolated rabbit jejunum preparations (5.0 mg/mL and shifted the Ca++ dose response curves towards right at concentration range of 0.3–1.0 mg/mL. Similarly, the extract application to isolated rabbit tracheal preparations relaxed the carbachol-(1 μM induced (0.3–1.0 mg/mL as well as K+-(80 mM induced contractions (3.0 mg/mL. Furthermore, it relaxed the phenylephrine (1 μM-induced contractions in isolated rabbit aorta preparations (3.0 mg/mL and K+ (80 mM-induced contractions (1.0 mg/mL. These effects were found comparable to that of dicyclomine, as an antagonist of muscarinic receptors as well as a possible Ca++ channel blocker. The previously mentioned findings may partially justify the folkloric use of Lactuca serriola in the management of conditions pertaining to spasm of intestine, bronchioles, and vasculature.

  17. Elucidating the genetic basis of antioxidant status in lettuce (Lactuca sativa).

    Science.gov (United States)

    Damerum, Annabelle; Selmes, Stacey L; Biggi, Gaia F; Clarkson, Graham Jj; Rothwell, Steve D; Truco, Maria José; Michelmore, Richard W; Hancock, Robert D; Shellcock, Connie; Chapman, Mark A; Taylor, Gail

    2015-01-01

    A diet rich in phytonutrients from fruit and vegetables has been acknowledged to afford protection against a range of human diseases, but many of the most popular vegetables are low in phytonutrients. Wild relatives of crops may contain allelic variation for genes determining the concentrations of these beneficial phytonutrients, and therefore understanding the genetic basis of this variation is important for breeding efforts to enhance nutritional quality. In this study, lettuce recombinant inbred lines, generated from a cross between wild and cultivated lettuce (Lactuca serriola and Lactuca sativa, respectively), were analysed for antioxidant (AO) potential and important phytonutrients including carotenoids, chlorophyll and phenolic compounds. When grown in two environments, 96 quantitative trait loci (QTL) were identified for these nutritional traits: 4 for AO potential, 2 for carotenoid content, 3 for total chlorophyll content and 87 for individual phenolic compounds (two per compound on average). Most often, the L. serriola alleles conferred an increase in total AOs and metabolites. Candidate genes underlying these QTL were identified by BLASTn searches; in several cases, these had functions suggesting involvement in phytonutrient biosynthetic pathways. Analysis of a QTL on linkage group 3, which accounted for >30% of the variation in AO potential, revealed several candidate genes encoding multiple MYB transcription factors which regulate flavonoid biosynthesis and flavanone 3-hydroxylase, an enzyme involved in the biosynthesis of the flavonoids quercetin and kaempferol, which are known to have powerful AO activity. Follow-up quantitative RT-PCR of these candidates revealed that 5 out of 10 genes investigated were significantly differentially expressed between the wild and cultivated parents, providing further evidence of their potential involvement in determining the contrasting phenotypes. These results offer exciting opportunities to improve the nutritional

  18. Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L.) cultivars and mapping genes.

    Science.gov (United States)

    Rauscher, Gilda; Simko, Ivan

    2013-01-22

    Lettuce (Lactuca sativa L.) is the major crop from the group of leafy vegetables. Several types of molecular markers were developed that are effectively used in lettuce breeding and genetic studies. However only a very limited number of microsattelite-based markers are publicly available. We have employed the method of enriched microsatellite libraries to develop 97 genomic SSR markers. Testing of newly developed markers on a set of 36 Lactuca accession (33 L. sativa, and one of each L. serriola L., L. saligna L., and L. virosa L.) revealed that both the genetic heterozygosity (UHe = 0.56) and the number of loci per SSR (Na = 5.50) are significantly higher for genomic SSR markers than for previously developed EST-based SSR markers (UHe = 0.32, Na = 3.56). Fifty-four genomic SSR markers were placed on the molecular linkage map of lettuce. Distribution of markers in the genome appeared to be random, with the exception of possible cluster on linkage group 6. Any combination of 32 genomic SSRs was able to distinguish genotypes of all 36 accessions. Fourteen of newly developed SSR markers originate from fragments with high sequence similarity to resistance gene candidates (RGCs) and RGC pseudogenes. Analysis of molecular variance (AMOVA) of L. sativa accessions showed that approximately 3% of genetic diversity was within accessions, 79% among accessions, and 18% among horticultural types. The newly developed genomic SSR markers were added to the pool of previously developed EST-SSRs markers. These two types of SSR-based markers provide useful tools for lettuce cultivar fingerprinting, development of integrated molecular linkage maps, and mapping of genes.

  19. Dietary Supplementation of Seaweed (Ulva lactuca to alleviate the Impact of Heat Stress in Growing Lambs

    Directory of Open Access Journals (Sweden)

    Kkalid A. Abdoun, Aly B. Okab, Ahmed M. El-Waziry, Emad M. Samara and Ahmed A. Al-Haidary

    2014-01-01

    Full Text Available Several environmental and nutritional management approaches have been used to mitigate heat stress and improve performance of farm animals in semi-arid and arid regions. The present study was designed with the intention to alleviate the negative effects of heat stress and to promote the performance of growing lambs reared under hot environmental conditions. The study was conducted on 18 male Naimey lambs with average body weight of 22.78±0.49 kg, and 4-5 months old. The animals were randomly divided into 3 equal groups (A, B and C, and fed diets containing different concentrations of seaweed (Ulva lactuca for 90 days. Group A served as control and was offered diet containing 0.0% seaweed. Groups B and C served as treated groups and were offered diets containing 3.0 and 5.0% seaweed, respectively. Dietary inclusion of seaweed to the diet of growing lambs exposed to heat stress (max Ta 43.9oC, max RH 81.1%, max THI 84.6 neither influenced (P>0.05 the thermo-physiological parameters (rectal and skin temperatures, nor affected (P>0.05 the performance parameters (feed intake, body weight gain, feed conversion efficiency. Furthermore, dietary seaweed supplementation did not alter (P>0.05 blood constituents or blood antioxidant capacity. However, dietary seaweed supplementation significantly (P<0.05 reduced respiratory rate, and increased serum potassium concentration. Based on the data of the present study, seaweed (Ulva lactuca supplementation to the diets of growing lambs reared under heat stress conditions did not show any indication of promoting their production performance or heat tolerance.

  20. Freqüência de enteroparasitas em amostras de alface (Lactuca sativa comercializadas em Lavras, Minas Gerais Frequency of intestinal parasites in samples of lettuce (Lactuca sativa commercialized in Lavras, Minas Gerais State

    Directory of Open Access Journals (Sweden)

    Antônio Marcos Guimarães

    2003-10-01

    Full Text Available O objetivo deste trabalho foi realizar uma avaliação parasitológica em amostras de alface (Lactuca sativa comercializadas em Lavras, MG. As amostras de alfaces apresentaram baixos padrões higiênicos, indicados pela presença de formas parasitológicas de origem animal ou humana e alta concentração de coliformes fecais.The aim of this study was to evaluate the parasitological contamination in samples of lettuce (Lactuca sativa commercialized in Lavras city, Minas Gerais. The samples of lettuce showed low hygienic conditions, indicated by the presence of parasites of animal or human origin and high concentration of fecal coliforms.

  1. Draft genome sequences of six neonatal meningitis-causing escherichia coli isolates (SP-4, SP-5, SP-13, SP-16, SP-46, and SP-65)

    Science.gov (United States)

    Neonatal meningitis Escherichia coli isolates (SP-4, SP-5, SP-13, SP-16, SP-46, and SP-65) were recovered from infants in the Netherlands from 1989 to 1997. Here, we report the draft genome sequences for these six E. coli isolates, which are currently being used to validate food safety processing te...

  2. ON THE IDENTITY OF KARLODINIUM VENEFICUM AND DESCRIPTION OF KARLODINIUM ARMIGER SP. NOV. (DINOPHYCEAE), BASED ON LIGHT AND ELECTRON MICROSCOPY, NUCLEAR-ENCODED LSU RDNA, AND PIGMENT COMPOSITION

    DEFF Research Database (Denmark)

    Bergholtz, Trine; Daugbjerg, Niels; Moestrup, Øjvind

    2006-01-01

    . The culture used by Ballantine to describe Gymnodinium veneficum Ballantine (Plymouth 103) was examined by light and electron microscopy and by partial LSU rDNA. Ultrastructurally, it proved identical to K. micrum (cultures Plymouth 207 and K. Tangen KT-77D, the latter also known as K-0522), and in LSU...

  3. Active packaging for fresh-cut iceberg lettuce (Lactuca sativa L. / Embalagem ativa para alface americana (Lactuca sativa L. minimamente processada

    Directory of Open Access Journals (Sweden)

    Fábio Yamashita

    2010-09-01

    Full Text Available The minimal processing of horticultural products endears the raw material and is convenient to the consumer due to the facility for preparing and consuming. The objective of this work was to develop an active packaging for fresh-cut iceberg lettuce (Lactuca sativa L. to increase its shelf life. Minimally processing methodology was defined and the product quality was determined by sensorial, physico-chemical and microbiological analysis. The lettuce tree was selected, trimmed, pre-washed, soaked in sanitized water (100ppm of active chlorine for 15 minutes and centrifuged. The lettuce leafs were packed in polypropylene pots with a sachet containing 1-methylcyclopropene (1-MCP and sealed with biodegradable starch film. Soon after the processing, the product was stored at 4oC for 12 days. Periodically samples were evaluated in terms of appearance and purchase intention, soluble solids and vitamin C contents, pH, texture, color, weight loss and total count of mesophilic and psicotrofic microorganisms, lactic bacteria, mould and yeast. Using 1-MCP in sachet format did not increase the lettuce shelf life but the minimal processing combined with packaging sealed with biodegradable film is practicable as the product showed good sensorial acceptance, low microbiological counts and shelf life of 5 days at 4oC.O processamento mínimo de produtos hortícolas agrega valor à matéria-prima e são convenientes ao consumidor, devido à facilidade de preparo e consumo. O objetivo do trabalho foi desenvolver uma embalagem ativa para alface americana (Lactuca sativa L. minimamente processada visando o aumento da vida útil. Foi definida uma metodologia de processamento mínimo e a qualidade do produto foi acompanhada através de avaliação sensorial, físico-química e microbiológica. As cabeças de alface foram desfolhadas, selecionadas, pré-lavadas, sanificadas (100 ppm de cloro ativo por 15 minutos e centrifugadas. As folhas foram acondicionadas em potes de

  4. Allelopathic effect of Raphanus sativus on Urochloa decumbens and Lactuca sativa = Efeito alelopático de Raphanus sativus em Urochloa decumbens e Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Rafael Navas

    2016-10-01

    Full Text Available The aim of this study was to evaluate the allelopathic potential of an extract from the leaves and roots of Raphanus sativus, on the species Urochloa decumbens and Lactuca sativa L. To obtain the extract, the leaves and roots of R. sativus were used separately, crushed at a proportion of 200 g of leaves to 1 L of water to give a crude aqueous extract (100%. Dilutions of 60%, 40% and 20%, and the control were produced from this extract. Seeds of U. decumbens and L. sativa were evenly distributed over two sheets of germitest paper, with four replications of 40 seeds each. Germination was evaluated at 7 and 14 days after sowing, together with the germination speed index (GSI, length of the shoots and roots, and dry weight. The design was completely randomised, and the values submitted to analysis of variance by F-test and regression analysis. The leaf extract gave a reduction in the germination of L. sativa at all tested doses. With application of the root extract, an increase was seen in germination, in the GSI and length of the radicle in U. decumbens at doses of from 40%. Moreover, with application of the leaf extract, the length of the shoot and radicle were also greater, irrespective of the dose applied. There was no effect from the treatments on the dry mass of the species. = Objetivou-se com este trabalho avaliar o potencial alelopático de extrato de folhas e raízes de Raphanus sativus, nas espécies Urochloa decumbens e Lactuca sativa L. Para obtenção do extrato, foram utilizadas separadamente folhas e raízes de R. sativus, trituradas na proporção de 200 g de folhas para 1 L de água, resultando no extrato aquoso bruto (100%. A partir desse extrato, foram realizadas as diluições de 60%, 40% e 20% e testemunha. Sementes de U. decumbens e L. sativa foram distribuídas uniformemente sobre duas folhas de papel germitest, com quatro repetições, com 40 sementes cada. As avaliações de germinação foram realizadas aos 7 e aos 14 dias

  5. Root Zone Cooling and Exogenous Spermidine Root-Pretreatment Promoting Lactuca sativa L. Growth and Photosynthesis in the High-Temperature Season

    Directory of Open Access Journals (Sweden)

    Jin eSun

    2016-03-01

    Full Text Available Root zone high-temperature stress is a major factor limiting hydroponic plant growth during the high-temperature season. The effects of root zone cooling (RZC; at 25°C and exogenous spermidine (Spd root-pretreatment (SRP, 0.1 mM on growth, leaf photosynthetic traits, and chlorophyll fluorescence characteristics of hydroponic Lactuca sativa L. grown in a high-temperature season (average temperature > 30°C were examined. Both treatments significantly promoted plant growth and photosynthesis in the high-temperature season, but the mechanisms of photosynthesis improvement in the hydroponic grown lettuce plants were different between the RZC and SRP treatments. The former improved plant photosynthesis by increasing stoma conductance (Gs to enhance CO2 supply, thus promoting photosynthetic electron transport activity and phosphorylation, which improved the level of the photochemical efficiency of photosystem II (PSII, rather than enhancing CO2 assimilation efficiency. The latter improved plant photosynthesis by enhancing CO2 assimilation efficiency, rather than stomatal regulation. Combination of RZC and SRP significantly improved PN of lettuce plants in a high-temperature season by both improvement of Gs to enhance CO2 supply and enhancement of CO2 assimilation. The enhancement of photosynthetic efficiency in both treatments was independent of altering light-harvesting or excessive energy dissipation.

  6. Metallic Nanoparticle (TiO2 and Fe3O4) Application Modifies Rhizosphere Phosphorus Availability and Uptake by Lactuca sativa.

    Science.gov (United States)

    Zahra, Zahra; Arshad, Muhammad; Rafique, Rafia; Mahmood, Arshad; Habib, Amir; Qazi, Ishtiaq A; Khan, Saud A

    2015-08-12

    Application of engineered nanoparticles (NPs) with respect to nutrient uptake in plants is not yet well understood. The impacts of TiO2 and Fe3O4 NPs on the availability of naturally soil-bound inorganic phosphorus (Pi) to plants were studied along with relevant parameters. For this purpose, Lactuca sativa (lettuce) was cultivated on the soil amended with TiO2 and Fe3O4 (0, 50, 100, 150, 200, and 250 mg kg(-1)) over a period of 90 days. Different techniques, such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Raman, and Fourier transform infrared spectroscopy (FTIR) were used to monitor translocation and understand the possible mechanisms for phosphorus (P) uptake. The trends for P accumulation were different for roots (TiO2 > Fe3O4 > control) and shoots (Fe3O4 > TiO2 > control). Cystine and methionine were detected in the rhizosphere in Raman spectra. Affinities of NPs to adsorb phosphate ions, modifications in P speciation, and NP stress in the rhizosphere had possibly contributed to enhanced root exudation and acidification. All of these changes led to improved P availability and uptake by the plants. These promising results can help to develop an innovative strategy for using NPs for improved nutrient management to ensure food security.

  7. Root Zone Cooling and Exogenous Spermidine Root-Pretreatment Promoting Lactuca sativa L. Growth and Photosynthesis in the High-temperature Season.

    Science.gov (United States)

    Sun, Jin; Lu, Na; Xu, Hongjia; Maruo, Toru; Guo, Shirong

    2016-01-01

    Root zone high-temperature stress is a major factor limiting hydroponic plant growth during the high-temperature season. The effects of root zone cooling (RZC; at 25°C) and exogenous spermidine (Spd) root-pretreatment (SRP, 0.1 mM) on growth, leaf photosynthetic traits, and chlorophyll fluorescence characteristics of hydroponic Lactuca sativa L. grown in a high-temperature season (average temperature > 30°C) were examined. Both treatments significantly promoted plant growth and photosynthesis in the high-temperature season, but the mechanisms of photosynthesis improvement in the hydroponic grown lettuce plants were different between the RZC and SRP treatments. The former improved plant photosynthesis by increasing stoma conductance (G s) to enhance CO2 supply, thus promoting photosynthetic electron transport activity and phosphorylation, which improved the level of the photochemical efficiency of photosystem II (PSII), rather than enhancing CO2 assimilation efficiency. The latter improved plant photosynthesis by enhancing CO2 assimilation efficiency, rather than stomatal regulation. Combination of RZC and SRP significantly improved P N of lettuce plants in a high-temperature season by both improvement of G s to enhance CO2 supply and enhancement of CO2 assimilation. The enhancement of photosynthetic efficiency in both treatments was independent of altering light-harvesting or excessive energy dissipation.

  8. Nitrous oxide emission from Ulva lactuca incubated in batch cultures is stimulated by nitrite, nitrate and light

    DEFF Research Database (Denmark)

    Albert, Kristian Rost; Bruhn, Annette; Ambus, Per

    2013-01-01

    Biomass yields from some species of macroalgae exceed the yields in traditional terrestrial production systems. This renewable carbon source possesses a potential for energy purposes and thus reduction in fossil fuel carbon dioxide (CO2) emissions. Previous experiments have indicated that nitrous...... oxide (N2O) may be produced by green algae. We investigated the N2O emissions in the green alga Ulva lactuca. Significant N2O emissions, along with CO2 uptake, were demonstrated from vital U. lactuca material from different natural populations incubated in the laboratory with nitrite (NO2−) and nitrate......2O production by algae emphasizes the need for experiments under natural conditions in order to evaluate potential greenhouse gas balances associated with large-scale productions for energy purposes....

  9. Biosorption of bovine serum albumin by Ulva lactuca biomass from industrial wastewater: Equilibrium, kinetic and thermodynamic study

    Energy Technology Data Exchange (ETDEWEB)

    Rathinam, Aravindhan [Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020 (India); Zou, Linda, E-mail: linda.zou@unisa.edu.au [SA Water Centre for Water Management and Reuse, University of South Australia, Mawson Lakes Campus, Adelaide, SA 5095 (Australia)

    2010-12-15

    Batch biosorption experiments have been carried out for the removal of bovine serum albumin (BSA) from simulated industrial wastewater onto Ulva lactuca seaweed. Various vital parameters influencing the biosorption process such as initial concentration of BSA, pH of the solution, adsorbent dosage and temperature have been determined. The biosorption kinetics follows a pseudo-second order kinetic model. Equilibrium isotherm studies demonstrate that the biosorption followed the Freundlich isotherm model, which implies a heterogeneous sorption phenomenon. Various thermodynamic parameters such as changes in enthalpy, free energy and entropy have been calculated. The positive value of {Delta}H{sup o} and the negative value of {Delta}G{sup o} show that the sorption process is endothermic and spontaneous. The positive value of change in entropy {Delta}S{sup o} shows increased randomness at the solid-liquid interface during the biosorption of BSA onto U. lactuca seaweed.

  10. Biosorption of bovine serum albumin by Ulva lactuca biomass from industrial wastewater: equilibrium, kinetic and thermodynamic study.

    Science.gov (United States)

    Rathinam, Aravindhan; Zou, Linda

    2010-12-15

    Batch biosorption experiments have been carried out for the removal of bovine serum albumin (BSA) from simulated industrial wastewater onto Ulva lactuca seaweed. Various vital parameters influencing the biosorption process such as initial concentration of BSA, pH of the solution, adsorbent dosage and temperature have been determined. The biosorption kinetics follows a pseudo-second order kinetic model. Equilibrium isotherm studies demonstrate that the biosorption followed the Freundlich isotherm model, which implies a heterogeneous sorption phenomenon. Various thermodynamic parameters such as changes in enthalpy, free energy and entropy have been calculated. The positive value of ΔH° and the negative value of ΔG° show that the sorption process is endothermic and spontaneous. The positive value of change in entropy ΔS° shows increased randomness at the solid-liquid interface during the biosorption of BSA onto U. lactuca seaweed. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Biosorption of bovine serum albumin by Ulva lactuca biomass from industrial wastewater: Equilibrium, kinetic and thermodynamic study

    International Nuclear Information System (INIS)

    Rathinam, Aravindhan; Zou, Linda

    2010-01-01

    Batch biosorption experiments have been carried out for the removal of bovine serum albumin (BSA) from simulated industrial wastewater onto Ulva lactuca seaweed. Various vital parameters influencing the biosorption process such as initial concentration of BSA, pH of the solution, adsorbent dosage and temperature have been determined. The biosorption kinetics follows a pseudo-second order kinetic model. Equilibrium isotherm studies demonstrate that the biosorption followed the Freundlich isotherm model, which implies a heterogeneous sorption phenomenon. Various thermodynamic parameters such as changes in enthalpy, free energy and entropy have been calculated. The positive value of ΔH o and the negative value of ΔG o show that the sorption process is endothermic and spontaneous. The positive value of change in entropy ΔS o shows increased randomness at the solid-liquid interface during the biosorption of BSA onto U. lactuca seaweed.

  12. Parasitos em alfaces (Lactuca sativa de mercados e feiras livres de Lages - Santa Catarina = Lettuces (Lactuca sativa parasites in markets and free fairs from Lages - Santa Catarina

    Directory of Open Access Journals (Sweden)

    Quadros, Rosiléia Marinho de

    2008-01-01

    Full Text Available Objetivo: avaliar a contaminação por parasitos de interesse em Saúde Pública em alfaces (Lactuca sativa comercializadas no município de Lages, Santa Catarina. Materiais e Métodos: Foi utilizado um processo de amostragem intencional, selecionando-se oito supermercados e duas feiras, de acordo com a abrangência e volume de vendas desses estabelecimentos para a cidade. Foram processadas 122 amostras de alfaces, pelas técnicas de sedimentação espontânea (Lutz, centrífugo-flutuação em sulfato de zinco (Faust, centrífugo-flutuação em solução de sacarose (Sheather e coloração de Ziehl Neelsen modificada. Resultados: O índice de parasitismo foi de 88,5% (108/122 com 77% (94/122 e 11,5% (14/122 para as amostras de supermercados e de feiras livres, respectivamente. A técnica de Lutz detectou 46,7% (57/122 de alfaces parasitadas; Sheather e Faust evidenciaram 31,1% (38/122 e 10,6% (13/122 de alfaces com ovos e/ou oocistos de parasitos, respectivamente. Predominaram os gêneros Eimeria, Giardia e Entamoeba. Conclusões: As amostras analisadas apresentaram baixos padrões higiênicos, necessitando de vigilância sanitária mais atuante na fiscalização de todas as etapas do processo produtivo de hortaliças

  13. Decontamination treatments to eliminate problem biota from macroalgal tank cultures ofOsmundea pinnatifida,Palmaria palmataandUlva lactuca.

    Science.gov (United States)

    Kerrison, Philip D; Le, Hau Nhu; Twigg, Gail C; Smallman, Duncan R; MacPhee, Rory; Houston, Fiona A B; Hughes, Adam D

    2016-01-01

    The effect of a range of chemical disinfectants at different concentration and exposure times was investigated on five macroalgal species and the marine gastropod Littorina spp. Palmaria palmata , Osmundea pinnatifida and Ulva lactuca are commercially valuable and are often cultivated in tanks for food or feed. Ectocarpus siliculosus and Ulva intestinalis are common epiphytes of P. palmata and O. pinnatifida cultures, whilst Littorina spp. are common herbivorous epibionts within U. lactuca culture tanks. These contaminants reduce the productivity and quality of the culture as a food. Differential tolerance to the treatments was seen between the algal species using pulse-amplitude modulation (PAM) chlorophyll a fluorescence, a few hours and a week following treatment. We identified treatments that selectively damaged the epiphyte but not the basiphyte species. Ectocarpus siliculosus had a significantly lower tolerance to 1 % sodium hypochlorite than P. palmata , and to 25 % methanol than O. pinnatifida , with a 1-5 min exposure appearing most suitable. Ulva intestinalis had a significantly lower tolerance than P. palmata and O. pinnatifida to many disinfectants: 0.1-1 % sodium hypochlorite for 10 min, 0.5 % potassium iodide for up to 10 min, and 0.25 % Kick-start (a commercial aquaculture disinfectant solution) for 1-5 min. No treatment was able to kill the gastropod snails without also damaging U. lactuca , although agitation in freshwater for an hr may cause them to detach from the basiphyte, with little to no photophysiological impact seen to U. lactuca . This experiment forms the basis for more extended commercial trials.

  14. The consumption of algae, Ulva lactuca, by the snail, Littorina littorea, in relation to colliery waste contamination

    Energy Technology Data Exchange (ETDEWEB)

    Davies, M.S.; Falconer, F. [University of Sunderland, Durham (United Kingdom). Centre of Ecology

    2001-07-01

    Colliery waste is a persistent contaminant of intertidal areas in north-east England where it can reduce biodiversity. In an attempt to understand the ways in which colliery waste exerts its effects, the authors tested how a common molluscan grazer (Littorina littorea) from a range of contaminated and uncontaminated sites reacts to a common macroalgal component of its diet (Ulva lactuca) from the same range of sites. It is hypothesised that algae that are exposed to colliery waste are rejected (eaten less) by snails than those algae that are not so exposed. It is also hypothesised that snails exposed to colliery waste would prefer (eat more) algae from contaminated sites and those animals not so exposed would prefer algae from uncontaminated sites. No differences in feeding were observed in relation to these hypotheses and it is concluded that the contamination of shores by colliery waste does not affect the feeding of L. littorea on U. lactuca. However, snails from contaminated sites ate significantly more algae than those from uncontaminated sites. This may be because of differential digestion or metabolism of the algae or because of a paucity of suitable macroalgae at contaminated sites, snails feeding heavily on the rare U. lactuca when it is encountered.

  15. Light and scanning electron microscopic studies of Myxobolus indica n. sp. and a report of three Myxozoan (Myxosporea: Bivalvulida parasites of cultured ornamental goldfish, Carassius auratus L. for the first time in India

    Directory of Open Access Journals (Sweden)

    Mandira Saha

    2017-08-01

    Full Text Available The ornamental fish industry is an economically viable sector in India which suffers from different ectoparasitic infestations, including the myxozoan parasites. An icthyoparasitological survey of myxozoan infections in ornamental fish farms in India revealed the presence of four myxozoan parasites belonging to the family Myxobolidae, in the genera Myxobolus and Thelohanellus. The myxozoan spores were small to large, spherical to ellipsoidal in size. The plasmodia measured 0.5–3.0 mm in diameter with disporic pansporoblasts and mature spores. During the survey the authors identified for the first time in India, three previously described species, namely, M. mehlhorni, T. nikolskii and T. batae; and one new species M. indica n. sp., all infecting the ornamental goldfish, Carassius auratus. The present study thus reports a new host, and a new locality for T. batae and M. mehlhorni. The description of T. nikolskii is the first record found in India. The spore of M. indica n. sp. measures 5.8 ± 0.2 × 4.1 ± 0.5 μm in size, having two equal shaped pyriform polar capsules measuring 4.1 ± 0.4 × 2.7 ± 0.6 μm. The results from a combination of light and scanning electron microscopic observations along with a comparison with closely related species were incorporated here. Molecular data is needed to complete the description of the new species.

  16. Sarcocystis calchasi sp. nov. of the domestic pigeon (Columba livia f. domestica) and the Northern goshawk (Accipiter gentilis): light and electron microscopical characteristics.

    Science.gov (United States)

    Olias, Philipp; Gruber, Achim D; Hafez, Hafez M; Heydorn, Alfred O; Mehlhorn, Heinz; Lierz, Michael

    2010-02-01

    A novel highly pathogenic Sarcocystis species has been shown to cycle between the Northern goshawk (Accipiter gentilis) as definitive host and the domestic pigeon (Columba livia f. domestica) as intermediate host. However, genetically based characteristics are only available from very few bird-infecting Sarcocystis species. We therefore further characterised morphological properties of this protozoan in both hosts. Using light and electron microscopy, oocysts and sporocysts as well as schizonts and sarcocysts were characterised and compared with available morphological features of previously reported Sarcocystis species of Northern goshawks, Columbidae and genetically closely related species of other avian hosts. Sporocysts shed from day 6 on after experimental infection by the Northern goshawk were of ovoid appearance (11.9 x 7.9 microm). Ultrastructurally, schizonts of all developmental stages were found in the liver, spleen and next to or in endothelial cells of various organs of domestic pigeons 7 to 12 days after experimental infection. The cyst wall surface of slender sarcocysts (1 to 2 mm in length and 20 to 50 microm in width) was smooth and lacked protrusions. Cystozoites were lancet-shaped and measured 7.5 x 1.5 microm in Giemsa stain smears. The morphological findings, when combined with data of experimental infection and genetic studies, convergently indicate that the recently discovered Sarcocystis species represents a new species. We therefore propose to name this parasite Sarcocystis calchasi species nova.

  17. A rapid and efficient in vitro regeneration system for lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Armas, Isabel; Pogrebnyak, Natalia; Raskin, Ilya

    2017-01-01

    Successful biotechnological improvement of crop plants requires a reliable and efficient in vitro regeneration system. Lettuce ( Lactuca sativa L.), one the most important vegetable crops worldwide, is strongly genotype-dependent in terms of regeneration capacity, limiting the potential for biotechnological improvement of cultivars which show recalcitrance under currently available protocols. The effect of different nutrient sources, plant hormone combinations and activated charcoal supplementation on shoot induction efficiency was evaluated on the cultivar 'RSL NFR', which had previously shown poor regeneration efficiency. Multiple shoot organogenesis from cotyledon explants was recorded at the highest frequency and speed on Murashige and Skoog regeneration medium supplemented with 200 mg/l of activated charcoal, 3% sucrose, 10 mg/l benzylaminopurine and 0.5 mg/l naphthaleneacetic acid, which induced shoots through direct regeneration in 90.8 ± 7.9% of explants. High shoot induction efficiency was also observed, albeit not quantified, when using this medium on some other cultivars. This activated charcoal-containing regeneration medium might offer a rapid and efficient option for direct shoot induction in some lettuce genotypes that do not respond well to common lettuce regeneration protocols. This is also the first report of the effect of activated charcoal in lettuce tissue culture.

  18. Ecotoxicological impact of two soil remediation treatments in Lactuca sativa seeds.

    Science.gov (United States)

    Rede, Diana; Santos, Lúcia H M L M; Ramos, Sandra; Oliva-Teles, Filipe; Antão, Cristina; Sousa, Susana R; Delerue-Matos, Cristina

    2016-09-01

    Pharmaceuticals have been identified as environmental emerging pollutants and are present in different compartments, including soils. Chemical remediation showed to be a good and suitable approach for soil remediation, though the knowledge in their impact for terrestrial organisms is still limited. Therefore, in this work, two different chemical remediation treatments (Fenton oxidation and nanoremediation) were applied to a soil contaminated with an environmental representative concentration of ibuprofen (3 ng g(-1)). The phytotoxic impact of a traditional soil remediation treatment (Fenton oxidation) and of a new and more sustainable approach for soil remediation (nanoremediation using green nano-scale zero-valent iron nanoparticles (nZVIs)) was evaluated in Lactuca sativa seeds. Percentage of seed germination, root elongation, shoot length and leaf length were considered as endpoints to assess the possible acute phytotoxicity of the soil remediation treatments as well as of the ibuprofen contaminated soil. Both chemical remediation treatments showed to have a negative impact in the germination and development of lettuce seeds, exhibiting a reduction up to 45% in the percentage of seed germination and a decrease around 80% in root elongation comparatively to the contaminated soil. These results indicate that chemical soil remediation treatments could be more prejudicial for terrestrial organisms than contaminated soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Semi-High Throughput Screening for Potential Drought-tolerance in Lettuce (Lactuca sativa) Germplasm Collections.

    Science.gov (United States)

    Knepper, Caleb; Mou, Beiquan

    2015-04-17

    This protocol describes a method by which a large collection of the leafy green vegetable lettuce (Lactuca sativa L.) germplasm was screened for likely drought-tolerance traits. Fresh water availability for agricultural use is a growing concern across the United States as well as many regions of the world. Short-term drought events along with regulatory intervention in the regulation of water availability coupled with the looming threat of long-term climate shifts that may lead to reduced precipitation in many important agricultural regions has increased the need to hasten the development of crops adapted for improved water use efficiency in order to maintain or expand production in the coming years. This protocol is not meant as a step-by-step guide to identifying at either the physiological or molecular level drought-tolerance traits in lettuce, but rather is a method developed and refined through the screening of thousands of different lettuce varieties. The nature of this screen is based in part on the streamlined measurements focusing on only three water-stress indicators: leaf relative water content, wilt, and differential plant growth following drought-stress. The purpose of rapidly screening a large germplasm collection is to narrow the candidate pool to a point in which more intensive physiological, molecular, and genetic methods can be applied to identify specific drought-tolerant traits in either the lab or field. Candidates can also be directly incorporated into breeding programs as a source of drought-tolerance traits.

  20. Isolation, biochemical characterization and antibiofilm effect of a lectin from the marine sponge Aplysina lactuca.

    Science.gov (United States)

    Carneiro, Rômulo Farias; Lima, Paulo Henrique Pinheiro de; Chaves, Renata Pinheiro; Pereira, Rafael; Pereira, Anna Luísa; de Vasconcelos, Mayron Alves; Pinheiro, Ulisses; Teixeira, Edson Holanda; Nagano, Celso Shiniti; Sampaio, Alexandre Holanda

    2017-06-01

    A new lectin was isolated from the marine sponge Aplysina lactuca (ALL) by combining ammonium sulfate precipitation and affinity chromatography on guar gum matrix. ALL showed affinity for the disaccharides α-lactose, β-lactose and lactulose (Ka=12.5, 31.9 and 145.5M -1 , respectively), as well as the glycoprotein porcine stomach mucin. Its hemagglutinating activity was stable in neutral acid pH values and temperatures below 60°C. ALL is a dimeric protein formed by two covalently linked polypeptide chains. The average molecular mass, as determined by Electrospray Ionization Mass Spectrometry (ESI-MS), was 31,810±2Da. ESI-MS data also indicated the presence of three cysteines involved in one intrachain and one interchain disulfide bond. The partial amino acid sequence of ALL was determined by tandem mass spectrometry. Eight tryptic peptides presented similarity with lectin I isolated from Axinella polypoides. Its secondary structure is predominantly β-sheet, as indicated by circular dichroism (CD) spectroscopy. ALL agglutinated gram-positive and gram-negative bacterial cells, and it were able to significantly reduce the biomass of the bacterial biofilm tested at dose- dependent effect. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Carotenoids of Lettuce (Lactuca sativa L. Grown on Soil Enriched with Spent Coffee Grounds

    Directory of Open Access Journals (Sweden)

    Susana Casal

    2012-02-01

    Full Text Available The impact of spent coffee grounds on carotenoid and chlorophyll content in lettuce (Lactuca sativa L. var. capitata was evaluated. A greenhouse pot experiment was conducted with spent coffee amounts ranging from 0% to 20% (v/v. All evaluated pigments increased proportionally to spent coffee amounts. Lutein and β-carotene levels increased up to 90% and 72%, respectively, while chlorophylls increased up to 61%. Biomass was also improved in the presence of 2.5% to 10% spent coffee, decreasing for higher amounts. Nevertheless, all plants were characterized by lower organic nitrogen content than the control ones, inversely to the spent coffee amounts, pointing to possible induced stress. Collected data suggests that plants nutritional features, with regards to these bioactive compounds, can be improved by the presence of low amounts of spent coffee grounds (up to 10%. This observation is particularly important because soil amendment with spent coffee grounds is becoming increasingly common within domestic agriculture. Still, further studies on the detailed influence of spent coffee bioactive compounds are mandatory, particularly regarding caffeine.

  2. Carotenoids of lettuce (Lactuca sativa L.) grown on soil enriched with spent coffee grounds.

    Science.gov (United States)

    Cruz, Rebeca; Baptista, Paula; Cunha, Sara; Pereira, José Alberto; Casal, Susana

    2012-02-07

    The impact of spent coffee grounds on carotenoid and chlorophyll content in lettuce (Lactuca sativa L. var. capitata) was evaluated. A greenhouse pot experiment was conducted with spent coffee amounts ranging from 0% to 20% (v/v). All evaluated pigments increased proportionally to spent coffee amounts. Lutein and β-carotene levels increased up to 90% and 72%, respectively, while chlorophylls increased up to 61%. Biomass was also improved in the presence of 2.5% to 10% spent coffee, decreasing for higher amounts. Nevertheless, all plants were characterized by lower organic nitrogen content than the control ones, inversely to the spent coffee amounts, pointing to possible induced stress. Collected data suggests that plants nutritional features, with regards to these bioactive compounds, can be improved by the presence of low amounts of spent coffee grounds (up to 10%). This observation is particularly important because soil amendment with spent coffee grounds is becoming increasingly common within domestic agriculture. Still, further studies on the detailed influence of spent coffee bioactive compounds are mandatory, particularly regarding caffeine.

  3. The Influence of biol in the crop yield of Lactuca sativa L. variety Iceberg

    Directory of Open Access Journals (Sweden)

    Pomboza-Tamaquiza Pablo

    2016-11-01

    Full Text Available The objective of the research was to assess the influence of biol enriched with efficient micro-organisms, in the ecological cultivation of Lactuca sativa L (lettuce variety "Iceberg". The field test was carried out on the farm of Querochaca, Faculty of Sciences Agriculture, of the Technical University of Ambato. The studied factors were doses of biol (2%, 4% and 6% and frequencies of application (8 and 15 days, I know used the experimental design of complete blocks at random, with factorial arrangement of 3x2 1 with three repetitions. We evaluated: plant height, diameter of the main stem, days to harvest, weight and diameter of the bud commercial, performance in kg/plot neta and performance in kg/experimental unit, conducted the significance test of Duncan to 5%. The results showed that the dose of 6 per cent applied every 15 days treatment D3F2, contributed to the larger diameter of the bud commercial (25.9 cm; the greater weight of cogollo commercial (1.14 kg and the higher performance (549 kg/experimental unit. This suggests that the implementation of biol can be an important ecological alternative to fertilize organic farming as the lettuce by reducing the use of fertilizers in chemical synthesis and production costs.

  4. Differential Responses of Two Lactuca sativa Varieties to Bicarbonate-Induced Iron Deficiency

    Directory of Open Access Journals (Sweden)

    Mohamed Chebbi

    2013-11-01

    Full Text Available Iron chlorosis induced by bicarbonate is very common in calcareous soils, where bicarbonate (HCO3- ions are present at high concentrations. In this study, morpho-physiological and biochemical responses of two Lactuca sativa varieties (Romaine and Vista to bicarbonate induced iron deficiency were investigated. The culture was conducted on nutrient solution containing 5 µM Fe and 10 mM NaHCO3, in a growth chamber with controlled conditions. After 14 days of bicarbonate treatment, the two varieties seedling showed a slight yellowing of young leaves associated with a significant decline of plant biomass, leaf number and area. Furthermore, the concentrations of the nutrient elements (potassium, magnesium, iron and calcium in leaves and roots of two lettuce varieties were modified. In roots of bicarbonate treated plants, the Fe-chelate reductase activity was increased as compared to control in both varieties. PEPC activity was enhanced only in Vista variety. Moreover, Fe deficiency induced a small change in the photosynthetic parameters and chlorophyll fluorescence, especially in Romaine variety. These changes are accompanied by decreases in ribulose 1.5-bisphosphate carboxylase/oxygenase (Rubisco activity. These findings indicated that Vista variety could survive at low iron supply.

  5. Evaluation of response of lettuce (Lactuca sativa L. to temperature and light stress

    Directory of Open Access Journals (Sweden)

    Nidal Tabit Shaban

    2016-06-01

    Full Text Available The aim of the study was to assess the effect of irrigation water temperature and shading on the rate of photosynthesis and transpiration in four varieties of lettuce (Lactuca sativa L. – green foliage (‘Salakis’ and ‘Estony’ and red foliage (‘Lollo Rossa’ and ‘Nika’. During the production of seedlings in the greenhouse, two irrigation water temperature regimes (12 and 20°C were applied. After transplanting in the field plants were grown under three lighting systems (100, 70, and 50% of lighting in the open. The rates of photosynthesis and transpiration were measured at the end of the greenhouse period and 14 days after shading in the field using a Li 6400 infrared gas analyzer. In most varieties, cooling of the irrigation water was not found to have an effect on the rate of photosynthesis. Plants of all the varieties responded to the decrease in irrigation water temperature and to strong shading by reducing transpiration and increasing the water use efficiency. The ‘Salakis’ and ‘Estony’ plants have shown the best adaptability to the changing conditions and therefore they could be used successfully in the practice of extending vegetative growth.

  6. Combination of minimal processing and irradiation to improve the microbiological safety of lettuce ( Lactuca sativa, L.)

    Science.gov (United States)

    Goularte, L.; Martins, C. G.; Morales-Aizpurúa, I. C.; Destro, M. T.; Franco, B. D. G. M.; Vizeu, D. M.; Hutzler, B. W.; Landgraf, M.

    2004-09-01

    The feasibility of gamma radiation in combination with minimal processing (MP) to reduce the number of Salmonella spp. and Escherichia coli O157:H7 in iceberg lettuce ( Lactuca sativa, L.) (shredded) was studied in order to increase the safety of the product. The reduction of the microbial population during the processing, the D10-values for Salmonella spp. and E. coli O157:H7 inoculated on shredded iceberg lettuce as well as the sensory evaluation of the irradiated product were evaluated. The immersion in chlorine (200 ppm) reduced coliform and aerobic mesophilic microorganisms by 0.9 and 2.7 log, respectively. D-values varied from 0.16 to 0.23 kGy for Salmonella spp. and from 0.11 to 0.12 kGy for E. coli O157:H7. Minimally processed iceberg lettuce exposed to 0.9 kGy does not show any change in sensory attributes. However, the texture of the vegetable was affected during the exposition to 1.1 kGy. The exposition of MP iceberg lettuce to 0.7 kGy reduced the population of Salmonella spp. by 4.0 log and E. coli by 6.8 log without impairing the sensory attributes. The combination of minimal process and gamma radiation to improve the safety of iceberg lettuce is feasible if good hygiene practices begins at farm stage.

  7. Efficient and stable transformation of Lactuca sativa L. cv. Cisco (lettuce) plastids.

    Science.gov (United States)

    Kanamoto, Hirosuke; Yamashita, Atsushi; Asao, Hiroshi; Okumura, Satoru; Takase, Hisabumi; Hattori, Masahira; Yokota, Akiho; Tomizawa, Ken-Ichi

    2006-04-01

    Transgenic plastids offer unique advantages in plant biotechnology, including high-level foreign protein expression. However, broad application of plastid genome engineering in biotechnology has been largely hampered by the lack of plastid transformation systems for major crops. Here we describe the development of a plastid transformation system for lettuce, Lactuca sativa L. cv. Cisco. The transforming DNA carries a spectinomycin-resistance gene (aadA) under the control of lettuce chloroplast regulatory expression elements, flanked by two adjacent lettuce plastid genome sequences allowing its targeted insertion between the rbcL and accD genes. On average, we obtained 1 transplastomic lettuce plant per bombardment. We show that lettuce leaf chloroplasts can express transgene-encoded GFP to approximately 36% of the total soluble protein. All transplastomic T0 plants were fertile and the T1 progeny uniformly showed stability of the transgene in the chloroplast genome. This system will open up new possibilities for the efficient production of edible vaccines, pharmaceuticals, and antibodies in plants.

  8. Allelopathic effect of medicinal plant Cannabis sativa L. on Lactuca sativa L. seed germination

    Directory of Open Access Journals (Sweden)

    Homa MAHMOODZADEH

    2015-11-01

    Full Text Available In order to examine allelopathic effect of Cannabis sativa L. on germination capability and seedling growth of Lactuca sativa L., a study was performed in laboratory conditions. Treatments were set up in randomised block design in four replications for each of four concentration ranges of 25, 50, 75 and 100 % of aqueous extract made of shoot parts and 4 identical extract concentrations made of root of cannabis. Control variant was lettuce seed treated by distilled water. During the studies shoot and seminal root length of lettuce seedlings were measured after treatments with different concentrations of extracts made of root and shoot parts of cannabis, and the obtained values were compared with the control. The obtained results suggest that the extract from the shoot parts of cannabis in high concentrations of 75 and 100 % had inhibiting effect to the germination indices while the extract from the root had no statistically significant effect on germination of lettuce seeds. Extract made of root part of cannabis showed also stimulatory effect to shoot and seminal root length of lettuce seedlings in extract concentrations of 50, 75 and 100 %.

  9. Toxicity of polyfluorinated and perfluorinated compounds to lettuce (Lactuca sativa) and green algae (Pseudokirchneriella subcapitata).

    Science.gov (United States)

    Ding, Guanghui; Wouterse, Marja; Baerselman, Rob; Peijnenburg, Willie J G M

    2012-01-01

    Recently, polyfluorinated and perfluorinated compounds (PFCs) have been detected in most surface waters around the world. Because some PFCs are persistent and tend to accumulate in surface waters, their potential adverse effects to aquatic organisms have received increasing attention. Nevertheless, currently available toxicity information is limited. The aim of this study was to evaluate the toxicity effects of seven PFCs on root elongation of lettuce (Lactuca sativa) and photosynthesis of green algae (Pseudokirchneriella subcapitata). It was found that the toxicity profiles of both species tested were similar and had good relations with the fluorinated carbon-chain length of the PFCs investigated. One of the compounds tested, perfluorobutanoic acid, was found to be more toxic than expected in the algae test, which may be related with acidification of the test solution. It was concluded that because short-chained PFCs are becoming the predominant PFC pollutants in surface waters, their long-term toxicity and mixture toxicity with other PFCs should be studied in greater detail.

  10. Zn-biofortification enhanced nitrogen metabolism and photorespiration process in green leafy vegetable Lactuca sativa L.

    Science.gov (United States)

    Barrameda-Medina, Yurena; Lentini, Marco; Esposito, Sergio; Ruiz, Juan M; Blasco, Begoña

    2017-04-01

    Excessive rates of nitrogen (N) fertilizers may result in elevated concentrations of nitrate (NO 3 - ) in plants. Considering that many programs of biofortification with trace elements are being performed, it has become important to study how the application of these elements affects plant physiology and, particularly, N utilization in leaf crops. The main objective of the present study was to determine whether the NO 3 - accumulation and the nitrogen use efficiency was affected by the application of different doses of Zn in Lactuca sativa plants. Zn doses in the range 80-100 µmol L -1 produced an increase in Zn concentration provoking a decrease of NO 3 - concentration and increase of the nitrate reductase, glutamine synthetase and aspartate aminotransferase activities, as well as the photorespiration processes. As result, we observed an increase in reduced N, total N concentration and N utilization efficiency. Consequently, at a dose of 80 µmol L -1 of Zn, the amino acid concentration increased significantly. Adequate Zn fertilization is an important critical player in lettuce, especially at a dose of 80 µmol L -1 of Zn, because it could result in an increase in the Zn concentration, a reduction of NO 3 - levels and an increase the concentration of essential amino acids, with all of them having beneficial properties for the human diet. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. Combination of minimal processing and irradiation to improve the microbiological safety of lettuce (Lactuca sativa, L.)

    Energy Technology Data Exchange (ETDEWEB)

    Goularte, L.; Martins, C.G.; Morales-Aizpurua, I.C.; Destro, M.T.; Franco, B.D.G.M.; Vizeu, D.M.; Hutzler, B.W.; Landgraf, M. E-mail: landgraf@usp.br

    2004-10-01

    The feasibility of gamma radiation in combination with minimal processing (MP) to reduce the number of Salmonella spp. and Escherichia coli O157:H7 in iceberg lettuce (Lactuca sativa, L.) (shredded) was studied in order to increase the safety of the product. The reduction of the microbial population during the processing, the D{sub 10}-values for Salmonella spp. and E. coli O157:H7 inoculated on shredded iceberg lettuce as well as the sensory evaluation of the irradiated product were evaluated. The immersion in chlorine (200 ppm) reduced coliform and aerobic mesophilic microorganisms by 0.9 and 2.7 log, respectively. D-values varied from 0.16 to 0.23 kGy for Salmonella spp. and from 0.11 to 0.12 kGy for E. coli O157:H7. Minimally processed iceberg lettuce exposed to 0.9 kGy does not show any change in sensory attributes. However, the texture of the vegetable was affected during the exposition to 1.1 kGy. The exposition of MP iceberg lettuce to 0.7 kGy reduced the population of Salmonella spp. by 4.0 log and E. coli by 6.8 log without impairing the sensory attributes. The combination of minimal process and gamma radiation to improve the safety of iceberg lettuce is feasible if good hygiene practices begins at farm stage.

  12. Internalization of Murine Norovirus 1 by Lactuca sativa during Irrigation ▿

    Science.gov (United States)

    Wei, Jie; Jin, Yan; Sims, Tom; Kniel, Kalmia E.

    2011-01-01

    Romaine lettuce (Lactuca sativa) was grown hydroponically or in soil and challenged with murine norovirus 1 (MNV) under two conditions: one mimicking a severe one-time contamination event and another mimicking a lower level of contamination occurring over time. In each condition, lettuce was challenged with MNV delivered at the roots. In the first case, contamination occurred on day one with 5 × 108 reverse transcriptase quantitative PCR (RT-qPCR) U/ml MNV in nutrient buffer, and irrigation water was replaced with virus-free buffer every day for another 4 days. In the second case, contamination with 5 × 105 RT-qPCR U/ml MNV (freshly prepared) occurred every day for 5 days. Virus had a tendency to adsorb to soil particles, with a small portion suspended in nutrient buffer; e.g., ∼8 log RT-qPCR U/g MNV was detected in soil during 5 days of challenge with virus inoculums of 5 × 108 RT-qPCR U/ml at day one, but sativa. PMID:21296944

  13. Phytotoxicity of 15 common pharmaceuticals on the germination of Lactuca sativa and photosynthesis of Chlamydomonas reinhardtii.

    Science.gov (United States)

    Pino, Ma Rosa; Muñiz, Selene; Val, Jonatan; Navarro, Enrique

    2016-11-01

    Pharmaceuticals reach terrestrial environments through the application of treated wastewaters and biosolids to agricultural soils. We have investigated the toxicity of 15 common pharmaceuticals, classified as nonsteroidal anti-inflammatory drugs (NSAIDs), blood lipid-lowering agents, β-blockers and antibiotics, in two photosynthetic organisms. Twelve pharmaceuticals caused inhibitory effects on the radicle and hypocotyl elongation of Lactuca sativa seeds. The EC 50 values obtained were in the range of 170-5656 mg L -1 in the case of the radicle and 188-4558 mg L -1 for the hypocotyl. Propranolol was the most toxic drug for both root and hypocotyl elongation, followed by the NSAIDs, then gemfibrozil and tetracycline. Other effects, such as root necrosis, inhibition of root growth and curly hairs, were detected. However, even at the highest concentrations tested (3000 mg L -1 ), seed germination was not affected. NSAIDs decreased the photosynthetic yield of Chlamydomonas reinhardtii, but only salicylic acid showed EC 50 values below 1000 mg L -1 . The first effects detected at low concentrations, together with the concentrations found in environmental samples, indicate that the use of biosolids and wastewaters containing pharmaceuticals should be regulated and their compositions assessed in order to prevent medium- and long-term impacts on agricultural soils and crops.

  14. Allelopathic and bioherbicidal potential of Cladonia verticillaris on the germination and growth of Lactuca sativa.

    Science.gov (United States)

    Tigre, R C; Silva, N H; Santos, M G; Honda, N K; Falcão, E P S; Pereira, E C

    2012-10-01

    Responses to germination and initial growth of Lactuca sativa (lettuce) submitted to organic extracts and purified compounds of Cladonia verticillaris ("salambaia") were analyzed in this work. The experiments were conducted in laboratory conditions using extracts and pure compounds at different concentrations. None of the assays showed any influence on the germination of L. sativa seeds using C. verticillaris extracts; however, modifications in leaf area and seedling hypocotyl and root development occurred. In the growth experiments, seedlings exposed to ether or acetone extract showed diminished hypocotyl growth in detriment to the root stimulus, compared to controls. Increases in extract concentrations led to the formation of abnormal seedlings. To determine the allelochemicals of C. verticillaris, its principal components, fumarprotocetraric and protocetraric acids, were isolated and then analyzed by high performance liquid chromatography (HPLC). When the seedlings were exposed to the two acids separately, presented increased leaf area at all concentrations. In contrast, hypocotyl and root stimulus was observed only in the presence of protocetraric acid at different concentrations. Fumarprotocetraric as well as protocetraric acids, isolated and purified from C. verticillaris and Parmotrema dilatatum respectively, influenced the development of L. sativa seedlings at high concentrations, indicating a possible bioherbicide potential of these acids. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  15. Assessment of genetic diversity in lettuce (Lactuca sativaL.) germplasm using RAPD markers.

    Science.gov (United States)

    Sharma, Shubhangi; Kumar, Pankaj; Gambhir, Geetika; Kumar, Ramesh; Srivastava, D K

    2018-01-01

    The importance of germplasm characterization is an important link between the conservation and utilization of plant genetic resources in various breeding programmes. In the present study, genetic variability and relationships among 25 Lactuca sativa L. genotypes were tested using random amplified polymorphic DNA (RAPD) molecular markers. A total of 45 random decamer oligonucleotide primers were examined to generate RAPD profiles, out of these reproducible patterns were obtained with 22 primers. A total of 87 amplicon were obtained, out of which all were polymorphic and 7 were unique bands. The level of polymorphism across genotypes was 100% as revealed by RAPD. Genetic similarity matrix, based on Jaccard's coefficients ranged from 13.7 to 84.10% indicating a wide genetic base. Dendrogram was constructed by unweighted pair group method with arithmetic averages method. RAPD technology could be useful for identification of different accessions as well as assessing the genetic similarity among different genotypes of lettuce. The study reveals the limited genetic base and the needs to diversify using new sources from the germplasm.

  16. Human Norovirus and Its Surrogates Induce Plant Immune Response in Arabidopsis thaliana and Lactuca sativa.

    Science.gov (United States)

    Markland, Sarah M; Bais, Harsh; Kniel, Kalmia E

    2017-08-01

    Human norovirus is the leading cause of foodborne illness worldwide with the majority of outbreaks linked to fresh produce and leafy greens. It is essential that we thoroughly understand the type of relationship and interactions that take place between plants and human norovirus to better utilize control strategies to reduce transmission of norovirus in the field onto plants harvested for human consumption. In this study the expression of gene markers for the salicylic acid (SA) and jasmonic acid (JA) plant defense pathways was measured and compared in romaine lettuce (Lactuca sativa) and Arabidopsis thaliana Col-0 plants that were inoculated with Murine Norovirus-1, Tulane Virus, human norovirus GII.4, or Hank's Balanced Salt Solution (control). Genes involving both the SA and JA pathways were expressed in both romaine lettuce and A. thaliana for all three viruses, as well as controls. Studies, including gene expression of SA- and JA-deficient A. thaliana mutant lines, suggest that the JA pathway is more likely involved in the plant immune response to human norovirus. This research provides the first pieces of information regarding how foodborne viruses interact with plants in the preharvest environment.

  17. Determination of Profenofos Pesticidal Residue in Lettuce (Lactuca sativa L. by Gas Chromatographic Method

    Directory of Open Access Journals (Sweden)

    Yohannes Alen

    2015-05-01

    Full Text Available The determination of profenofos pesticidal residue in the lettuce (Lactuca sativa L. by using gas chromatography using flame photometric detector (FPD had been investigated. The lettuce was collected from Padang Luar area, Agam distric, West Sumatera. Sample for determination of profenofos residue divided into three groups: unwashed (A, washed with water (B, and washed with detergent (C. Maceration with sonication was used for the extraction using ethylacetateas a solvent. The results showed that profenofos pesticide residue in sample A, B and C were 0.204, 0.080 and 0.061 ppm, respectively. These profenofos pesticidal residue are over than the Maximum Residue Limits (MRL that established by The Japan Food Chemical Research Foundation (0.05 ppm even though World Health Organization (WHO has not established Maximum Residue Limits (MRL profenofos on lettuce. Based on the statistical analysis one-way method (Anova using SPSS 20.0 showed that there was a significant concentrations difference between lettuce A from lettuce B and lettuce C with p < 0.05.

  18. Structure and cytotoxic activity of ulvan extracted from green seaweed Ulva lactuca.

    Science.gov (United States)

    Thanh, Thi Thu Thuy; Quach, Thi Minh Thu; Nguyen, Thi Nu; Vu Luong, Dang; Bui, Minh Ly; Tran, Thi Thanh Van

    2016-12-01

    The structure of an ulvan obtained by water extraction from green seaweed Ulva lactuca was elucidated by using IR, NMR, SEC-MALL and ESIMS methods. The ulvan was also evaluated for its cytotoxic effects on three human cancer cell lines. The results showed that the ulvan was composed of rhamnose, galactose, xylose, manose, glucose (with a mole ratio of Rha: Gal: Xyl: Man: Glu equal to 1: 0.03: 0.07: 0.01: 0.06), uronic acid (21.5%) and sulfate content (18.9%) with a molecular weight of 347000. This ulvan mainly consists of disaccharide [→4)-β-d-GlcA-(1→4)-α-l-Rha3S-(1→] and other minor disaccharide β-GlcA-(1→2)-α-Xyl and β-GlcA-(→2)-α-Rha. The ulvan showed a significant cytotoxic activity against hepatocellular carcinoma (IC 50 29.67±2.87μg/ml), human breast cancer (IC 50 25.09±1.36μg/ml), and cervical cancer (IC 50 36.33±3.84μg/ml). Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Production and characterization of cyanocobalamin-enriched lettuce (Lactuca sativa L.) grown using hydroponics.

    Science.gov (United States)

    Bito, Tomohiro; Ohishi, Noriharu; Hatanaka, Yuka; Takenaka, Shigeo; Nishihara, Eiji; Yabuta, Yukinori; Watanabe, Fumio

    2013-04-24

    When lettuces (Lactuca sativa L.) grown for 30 days in hydroponic culture were treated with various concentrations of cyanocobalamin for 24 h, its content in their leaves increased significantly from nondetectable to 164.6 ± 74.7 ng/g fresh weight. This finding indicated that consumption of only two or three of these fresh leaves is sufficient to meet the Recommended Dietary Allowance for adults of 2.4 μg/day. Analyses using a cobalamin-dependent Escherichia coli 215 bioautogram and LC/ESI-MS/MS demonstrated that the cyanocobalamin absorbed from the nutrient solutions by the leaves did not alter any other compounds such as coenzymes and inactive corrinoids. Gel filtration indicated that most (86%) of the cyanocobalamin in the leaves was recovered in the free cyanocobalamin fractions. These results indicated that cyanocobalamin-enriched lettuce leaves would be an excellent source of free cyanocobalamin, particularly for strict vegetarians or elderly people with food-bound cobalamin malabsorption.

  20. Control in vitro de Botrytis (Botrytis cinerea), Mildiu (Bremia lactucae) Y Esclerotinia (Sclerotinia sclerotiorum) en lechuga (Lactuca sativa), usando extractos de Cola de Caballo (Equisetum arvense), Ortiga (Urtica dioica L.), Ruda (Ruta graveolens) y Tomillo (Thymus vulgaris).

    OpenAIRE

    Tayupanta Rodríguez, Verónica Vanessa

    2013-01-01

    Se realizó el control biológico de Botrytis cinerea, Bremia lactucae y Sclerotinia sclerotiorum, con 4 extractos de plantas: Ruta graveolens, Thymus vulgaris, Urtica dioica, Equisetum arvense y Trichoderma harzianum como tratamiento adicional. Se realizaron ensayos en laboratorio dentro de cajas Petri, donde se inoculó el hongo obtenido previamente en cultivo puro, junto con los extractos de cada planta para evaluar el halo de inhibición y se realizó el conteo del número de UFC (Unidades f...

  1. An evaluation of the toxicity and bioaccumulation of cisplatin in the marine environment using the macroalga, Ulva lactuca

    International Nuclear Information System (INIS)

    Easton, Cecilia; Turner, Andrew; Sewell, Graham

    2011-01-01

    The cytotoxic drug, cisplatin (cis-PtCl 2 (NH 3 ) 2 ), has been added to cultures of the marine macroalga, Ulva lactuca, under various experimental conditions. Both accumulation and internalisation over a 48 h period was greater when cisplatin was added to coastal sea water (salinity = 33) from a distilled water solution than when added to either sea water or estuarine water (salinity = 16.5) from a saline solution. This effect is attributed to the greater abundance of the more reactive monoaqua complex (cis-PtCl(OH 2 )(NH 3 ) 2 + ) in the distilled water solution and kinetic constraints on its conversion back to cis-PtCl 2 (NH 3 ) 2 in sea water. Despite its mode of action at the cellular level, cisplatin added up to concentrations of 150 nM did not incur a measurable reduction in the efficiency of photochemical energy conversion under any of experimental conditions tested. - Highlights: → This study is the first to examine the biogeochemistry and toxicity of a cytotoxic drug in the marine environment. → Cisplatin is accumulated and internalised by the marine macroalga, Ulva lactuca. → Accumulation is greater when the drug is administered from a distilled water solution than from a saline solution. → Results are consistent with the greater abundance of the more reactive aquated complexes in pure water. → Cisplatin is not phytotoxic to the alga over the concentration range (<150 nM) studied. - The cytotoxic drug, cisplatin, is accumulated and internalised by the marine macroalga, Ulva lactuca, but is not phytotoxic up to concentrations of 150 nM

  2. Chemical compositions of the marine algae Gracilaria salicornia (Rhodophyta) and Ulva lactuca (Chlorophyta) as a potential food source.

    Science.gov (United States)

    Tabarsa, Mehdi; Rezaei, Masoud; Ramezanpour, Zohreh; Waaland, Joseph Robert

    2012-09-01

    The nutritional compositions of two edible red (Gracilaria salicornia) and green (Ulva lactuca) seaweeds were determined to evaluate their possible uses as potential food ingredients. In general, these species contained limited amounts of lipids ranging between 0.99 and 2.00 g 100 g(-1) dry weight) and considerably high amount of minerals, especially in G. salicornia (38.91 g 100 g(-1) d.w.). The crude protein values varied between 9.58 and 10.69 g 100 g(-1) d.w. Amounts for total amino acids were 889.78 ± 22.64 mg g(-1) protein d.w. in G. salicornia and 543.3 ± 15.14 mg g(-1) protein d.w. in U. lactuca. The most abundant fatty acids were C12:0, C16:0, C20:4 ω6 and C22:5 ω3, in addition to C18:1 in G. salicornia. Both seaweed species were balanced sources of ω3 and ω6 fatty acids with a ratio of ω6/ω3 that varied between 1.2 and 1.17. Between the seaweeds investigated, high levels of K (2414.02-11 380.06 mg 100 g(-1) d.w.) were observed and the amounts of Ca, Na and Fe were higher than those reported for land plants. Thus, G. salicornia and U. lactuca may be utilised as value-added products for human nutrition purposes. Copyright © 2012 Society of Chemical Industry.

  3. PENGARUH MACAM MULSA DAN DOSIS PUPUK KANDANG AYAM TERHADAP HASIL TANAMAN SELADA (Lactuca sativa, L.) VAR. NEW GRAND RAPID

    OpenAIRE

    Herumia, Mia; Haryono, Gembong; Susilowati, Yulia Eko

    2017-01-01

    The research on the effect of mulch kinds and the effect of chiken manure doses to the lettuce yield (Lactuca sativa, L.) var New Grand Rapid. Experiment conducted in August until October 2016. Location of experiment in Dukuhan, Sumber, Dukuh, Magelang. The latitude is 663 m. The soils regosol with pH 6,3. The research method used factorial experiment (3x4) arranged in a randomized complete block design with three blocks. The first factor is mulch kind, transparant plastic mulch, black silver...

  4. Effect of dietary seaweed (Ulva lactuca) supplementation on growth performance of sheep and on in vitro gas production kinetics

    OpenAIRE

    EL-WAZIRY, Ahmed; AL-HAIDARY, Ahmed; OKAB, Aly; SAMARA, Emad; ABDOUN, Khalid

    2015-01-01

    This study was carried out to determine the effect of dietary seaweed (Ulva lactuca) supplementation on growth performance of sheep, in vitro gas production, estimated energy, and microbial protein synthesis. A total of 18 Naimey male sheep with average live weight of 22.78 ± 0.24 kg were randomly allocated to 3 groups. Sheep in group 1 were fed a diet containing commercial feed without seaweed as a control diet, sheep in group 2 were fed the control diet with 3% seaweed, and sheep in group 3...

  5. Germination and growth of lettuce (Lactuca sativa) at low atmospheric pressure

    Science.gov (United States)

    Spanarkel, Robert; Drew, Malcolm C.

    2002-01-01

    The response of lettuce (Lactuca sativa L. cv. Waldmann's Green) to low atmospheric pressure was examined during the initial 5 days of germination and emergence, and also during subsequent growth to vegetative maturity at 30 days. Growth took place inside a 66-l-volume low pressure chamber maintained at 70 kPa, and plant response was compared to that of plants in a second, matching chamber that was at ambient pressure (approximately 101 kPa) as a control. In other experiments, to determine short-term effects of low pressure transients, plants were grown at ambient pressure until maturity and then subjected to alternating periods of 24 h of low and ambient atmospheric pressures. In all treatments the partial pressure of O2 was maintained at 21 kPa (approximately the partial pressure in air at normal pressure), and the partial pressure of CO2 was in the range 66.5-73.5 Pa (about twice that in normal air) in both chambers, with the addition of CO2 during the light phase. With continuous exposure to low pressure, shoot and root growth was at least as rapid as at ambient pressure, with an overall trend towards slightly greater performance at the lower pressure. Dark respiration rates were greater at low pressure. Transient periods at low pressure decreased transpiration and increased dark respiration but only during the period of exposure to low pressure. We conclude that long-term or short-term exposure to subambient pressure (70 kPa) was without detectable detriment to vegetative growth and development.

  6. RESPON DUA VARIETAS TANAMAN SELADA (Lactuca sativa L. TERHADAP MACAM NUTRISI PADA SISTEM HIDROPONIK

    Directory of Open Access Journals (Sweden)

    Catur Wasonowati

    2013-03-01

    Full Text Available Lettuce (Lactuca sativa L is a common vegetables crops grown in the highland and lowlands.  A sample hydroponic lettuce cultivation provides an sources an alternative for farmers who have a narrow area, so that can server as an adequate source of income.  Providing nutrients to the two varienties of lettuce are expected to yield maximum production.  This tudy aims to determine the effect of nutrients on two varieties of lettuce plants.            The study was conducted in the greenhouse Agroekoteknologi Departement Faculty of Agriculture, University Trunojoyo Madurese from January to March 2011.  The method used was a factorial experiment based on Completely Randomized Design (CRD with three replicates consisting of two treatment factors, the first factor are two different varieties of lecctuce and the second factor are two differwnt kinds of nutrients.            The results showed that the chief varieties of butter (V1 produces the number of leaves and dry biomass is higher than the varieties of cos (V2.  Nutrition in V1 generate the number of leaves, wet biomass, dry biomass, and root length was higher than without the provision of (N0. V1 responses to nutrient hidrogroup (N1 resulted in higher leaf number than nutrition greentonik (N2, but the provision of dry biomass yield N2 higher than N1. Nutrition on V2 generate the number of leaves, wet biomass and dry biomass was higher than N0. V2 response to the provision of N1 and N2 produce the number of leaves, wet biomass, dry biomass, and root length are not significantly different.Key word : lettuce, varieties, nutrition, simple hydroponics

  7. [Calcium distribution in the central cell of lettuce (Lactuca sativa L.) before and after pollination].

    Science.gov (United States)

    Qiu, Yi Lan; Liu, Ru Shi; Ye, Lv; Tian, Hui

    2008-02-01

    Potassium antimonite precipitation was used to locate calcium in the central cell of lettuce (Lactuca sativa L.) before and after pollination. At 3d before anthesis, two polar nuclei of central cell separately located at two polarity of the cell, and few calcium precipitates (ppts) appeared in the polar nuclei and cytoplasm, but some ppts in its small vacuoles. At 2d before anthesis, two polar nuclei moved toward the middle of the cell and fused to form a secondary nucleus, and the ppts evidently increased in the nucleus and cytoplasm. At 1d before anthesis, secondary nucleus again moved toward micropylar end and located near the egg to prepare for fertilization. Calcium precipitates were mainly accumulated in the secondary nucleus. After pollination and before fertilization, the distribution of calcium ppts was similar to that before pollination. At 4h after pollination, the central cell was fertilized, and calcium ppts evidently increased in the cell and numerous were accumulated in its nucleus and cytoplasm. At 6h after pollination, the primary endosperm nucleus completed its first division and formed two dissociate endosperm nuclei, and still many calcium precipitates appeared in the nucleus and cytoplasm. With endosperm development, calcium ppts decreased in the endosperm cell. At 1d after emasculated and without pollination, the secondary nucleus of the cell still bordered on the egg and some calcium ppts appeared in the secondary nucleus. The results indicated that the temporal and spatial changes of calcium in the central cell may play an important physiological role during the development of the central cell and endosperm.

  8. PENGARUH KONSENTRASI KALIUM NITRAT PADA MEDIA VERMIKOMPOS TERHADAP KANDUNGAN HARA DAN TRUBUS SELADA (LACTUCA SATIVA L.

    Directory of Open Access Journals (Sweden)

    H. J. NAMSERNA

    2012-11-01

    Full Text Available The Effect of Potassium Nitrate Concentration in Vermicompost Medium on Nutrients Content and Shoot of Lettuce (Lactuca sativa L. The content of nitrogen and potassium in vermicompost generally low, i.e. less than two percent, so that still require the addition of another source to meet crop requirement. Potassium nitrate to form the ions K+ and NO3 6 after disolved in water so as to be readily available to plants. The study aims to determine the effect of the addition of potassium nitrate in the growth medium made from vermicompost to increase growth lettuce plant and know the critical level of concentration or nutrient solution electrical conductivity with the addition of potassium nitrate to the lettuce plant. Research conducted in the form of pot experiment. Experiment using Randomized Complete Block Design (RCBD with three replications. The treatment consists of 12 levels of concentration or nutrient solution electrical conductivity with the addition of potassium nitrate. The results of experiment indicated that addition of KNO3 highly significant effect on the increasing in fresh and dry weight of shoot per plant. Fresh and dry weight of shoot per plant were significantly increased in a quadratic with increasing concentrations of KNO3. The concentration of KNO3 are optimum for growth of plant shoot weight was at 12.23 g in 100l of water or electrical conductivity equivalent to 2.01 dS.m-1. The concentrations of P and K in plant shoot tissue were significantly increased linearly with the provision of KNO3. The concentration N, Ca, Mg, S, Na, Fe, Mn, Cu, Zn, Al and B in shoot tissue of plants is not affected KNO3.

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

    Science.gov (United States)

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

    2016-12-01

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

  10. [Enteroparasite determination in Lactuca sativa from farms dedicated to its production in Pasto, Colombia].

    Science.gov (United States)

    Polo, Giovanni Andrés; Benavides, Carmenza Janneth; Astaiza, Juan Manuel; Vallejo, Dario Antonio; Betancourt, Patricia

    2016-12-01

    Currently, vegetables like lettuce are widely recommended as part of the daily diet given their high nutritional value; however, while consumers feel attracted to the benefits provided by the vegetable, they may also be exposed to parasitic intestinal infections. To determine the presence or absence of enteroparasites in lettuce (Lactuca sativa) grown in the rural area in the municipality of Pasto, and to analyze associated factors based on the characterization of the lands. We conducted a descriptive double blind cross-sectional study. We took a total of 105 samples from 21 properties from June to December, 2013, and we processed them by sedimentation and flotation tests. Additionally, the owners were surveyed in order to obtain information about the possible variables influencing the occurrence of enteroparasites. We detected contamination in 100% of the lettuce samples and we found parasite eggs and larvae as follows: 95.25% with Entamoeba spp. cysts; 71.43% with Isospora spp. oocysts; 61.90% with Strongyloides stercoralis larvae (L3); 28.57% with Toxocara spp. eggs, and 4.76% with Eimeria spp. oocysts. Using the chi-square test we found association between Entamoeba spp. and ditches (p=0.008), dogs (p=0.008) and septic tanks (p=0.029); between Isospora spp. and compost (p=0.0001), dogs (p=0.0001) and slugs (p=0.002); between S. stercoralis and handling (p=0.003), and between Toxocara spp. and no use of biodigesters (p= 0.002). We found contamination with enteroparasites in lettuce samples from growing areas in the municipality of Pasto with animal and human sources as their main reservoirs, although others were present in the environment.

  11. Effect of soil cadmium on growth, photosynthesis and quality of Raphanus sativus and Lactuca sativa.

    Science.gov (United States)

    Kaur, Navjyot; Jhanji, Shalini

    2016-09-01

    Cadmium (Cd) raises serious concerns as its accumulation in the plant not only affect the growth and quality of plant but also threaten the health of consumers. In this research, two vegetables, i.e., radish (Raphanus sativus L.) and lettuce (Lactuca sativa L), were planted in pots having soil treated with Cd as Cd (NO3)2 at different doses (25, 50, 100 and 200 mg Cd kg-1 soil ) to investigate the influence of cadmium on their growth, photosynthetic attributes and quality. Cadmium retarded plant growth as dry weight of radish roots decline by 87% and leaves by 83% following 200 mg Cd kg-1 soil application and the corresponding values for lettuce were 64 and 69% respectively. Significant reductions in various photosynthetic parameters viz., leaf area per plant, total chlorophyll, Chl a and Chl b content were also recorded with Cd applications. The Cd treatments resulted in loss of membrane integrity as revealed by significant increase in electrolyte leakage in leaves of both vegetables. There was significant increase in Cd accumulation in radish and lettuce with all applications but no visual symptoms of Cd toxicity were noticed with 25 and 50 mg Cd kg-1 soil application except for yield differences, illustrating that Cd accumulate in this crop without visual evidence of its presence. However, toxicity symptoms in the form of interveinal chlorosis of the leaf lamina, followed by necrosis and leaf rolling, were clearly evident with 100 and 200 mg Cd kg-1 soil application. Apparently, Cd causes harm due to its phytotoxic effects and high accumulation in edible parts of radish and lettuce without any visible symptoms that constitutes a substantial hazard to human health.

  12. Uptake and phytotoxic effect of benzalkonium chlorides in Lepidium sativum and Lactuca sativa.

    Science.gov (United States)

    Khan, Adnan Hossain; Libby, Mark; Winnick, Daniel; Palmer, John; Sumarah, Mark; Ray, Madhumita B; Macfie, Sheila M

    2018-01-15

    Cationic surfactants such as benzalkonium chlorides (BACs) are used extensively as biocides in hospitals, food processing industries, and personal care products. BACs have the potential to reach the rooting zone of crop plants and BACs might thereby enter the food chain. The two most commonly used BACs, benzyl dimethyl dodecyl ammonium chloride (BDDA) and benzyl dimethyl tetradecyl ammonium chloride (BDTA), were tested in a hydroponic system to assess the uptake by and phytotoxicity to lettuce (Lactuca sativa L.) and garden cress (Lepidium sativum L.). Individually and in mixture, BACs at concentrations up to 100 mg L -1 did not affect germination; however, emergent seedlings were sensitive at 1 mg L -1 for lettuce and 5 mg L -1 for garden cress. After 12 d exposure to 0.25 mg L -1 BACs, plant dry weight was reduced by 68% for lettuce and 75% for garden cress, and symptoms of toxicity (necrosis, chlorosis, wilting, etc.) were visible. High performance liquid chromatography-mass spectroscopy analysis showed the presence of BACs in the roots and shoots of both plant species. Although no conclusive relationship was established between the concentrations of six macro- or six micro-nutrients, growth inhibition or BAC uptake, N and Mg concentrations in BAC-treated lettuce were 50% lower than that of control, indicating that BACs might induce nutrient deficiency. Although bioavailability of a compound in hydroponics is significantly higher than that in soil, these results confirm the potential of BACs to harm vascular plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Effect of acaricidal components isolated from lettuce (Lactuca sativa) on carmine spider mite (Tetranychus cinnabarinus Boisd.).

    Science.gov (United States)

    Li, M; Zhang, Y; Ding, W; Luo, J; Li, S; Zhang, Q

    2017-08-14

    This study aimed to evaluate the acaricidal activity of lettuce (Lactuca sativa) extracts against carmine spider mites (Tetranychus cinnabarinus Boisd.) and isolate the acaricidal components. Acaricidal activities of lettuce extracts isolated from different parts (the leaf, root and seed) using various solvents (petroleum ether, acetone and methanol) were evaluated with slide-dip bioassay and relatively high median lethal concentration (LC50) values were detected. Acetone extracts of lettuce leaves harvested in July and September were fractionated and isolated with silica gel and thin-layer chromatography. Consequently, acetone extracts of lettuce leaves harvested in July exhibited higher acaricidal activity than those harvested in September, with an LC50 value of 0.268 mg ml-1 at 72 h post-treatment. A total of 27 fractions were obtained from the acetone extract of lettuce leaves harvested in July, and mite mortalities with the 11th and 12th fractions were higher than those with the other 25 fractions (LC50: 0.751 and 1.258 mg ml-1 at 48 h post-treatment, respectively). Subsequently, active acaricidal components of the 11th fraction were identified by infrared, nuclear magnetic resonance and liquid chromatography/mass spectrometry. Five components were isolated from the 11th fraction, with components 11-a and 11-b showing relatively high acaricidal activities (LC50: 0.288 and 0.114 mg ml-1 at 48 h post-treatment, respectively). Component 11-a was identified as β-sitosterol. In conclusion, acetone extracts of lettuce leaves harvested in July might be used as a novel phytogenic acaricide to control mites.

  14. Phytohormone profile in Lactuca sativa and Brassica oleracea plants grown under Zn deficiency.

    Science.gov (United States)

    Navarro-León, Eloy; Albacete, Alfonso; Torre-González, Alejandro de la; Ruiz, Juan M; Blasco, Begoña

    2016-10-01

    Phytohormones, structurally diverse compounds, are involved in multiple processes within plants, such as controlling plant growth and stress response. Zn is an essential micronutrient for plants and its deficiency causes large economic losses in crops. Therefore, the purpose of this study was to analyse the role of phytohormones in the Zn-deficiency response of two economically important species, i.e. Lactuca sativa and Brassica oleracea. For this, these two species were grown hydroponically with different Zn-application rates: 10 μM Zn as control and 0.1 μM Zn as deficiency treatment and phytohormone concentration was determined by U-HPLC-MS. Zn deficiency resulted in a substantial loss of biomass in L. sativa plants that was correlated with a decline in growth-promoting hormones such as indole-3-acetic acid (IAA), cytokinins (CKs), and gibberellins (GAs). However these hormones increased or stabilized their concentrations in B. oleracea and could help to maintain the biomass in this species. A lower concentration of stress-signaling hormones such as ethylene precursor aminocyclopropane-1-carboxylic acid (ACC), abscisic acid (ABA), salicylic acid (SA) and jasmonic acid (JA) and also CKs might be involved in Zn uptake in L. sativa while a rise in GA4, isopentenyl adenine (iP), and ACC and a fall in JA and SA might contribute to a better Zn-utilization efficiency (ZnUtE), as observed in B. oleracea plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Evaluation of zinc oxide nanoparticles on lettuce (Lactuca sativa L.) growth and soil bacterial community.

    Science.gov (United States)

    Xu, Jiangbing; Luo, Xiaosan; Wang, Yanling; Feng, Youzhi

    2018-02-01

    The wide spread of nanoparticles (NPs) has caused tremendous concerns on agricultural ecosystem. Some metallic NPs, such as zinc oxide (ZnO), can be utilized as a nano-fertilizer when used at optimal doses. However, little is known about the responses of plant development and concomitant soil bacteria community to ZnO NPs. The present pot experiment studied the impacts of different doses of ZnO NPs and bulk ZnO (0, 1, 10, 100 mg ZnO/kg), on the growth of lettuce (Lactuca sativa L.) and the associated rhizospheric soil bacterial community. Results showed that at a dose of 10 mg/kg, ZnO NPs and bulk ZnO, enhanced the lettuce biomass and the net photosynthetic rate; whereas, the Zn content in plant tissue was higher in NPs treatment than in their bulk counterpart at 10 mg/kg dose or higher. For the underground observations, 10 mg/kg treatment doses (NPs or bulk) significantly changed the soil bacterial community structure, despite the non-significant variations in alpha diversity. Taxonomic distribution revealed that some lineages within Cyanobacteria and other phyla individually demonstrated similar or different responses to ZnO NPs and bulk ZnO. Moreover, some lineages associated with plant growth promotion were also influenced to different extents by ZnO NPs and bulk ZnO, suggesting the distinct microbial processes occurring in soil. Collectively, this study expanded our understanding of the influence of ZnO NPs on plant performance and the associated soil microorganisms.

  16. Exogenous Glycine Nitrogen Enhances Accumulation of Glycosylated Flavonoids and Antioxidant Activity in Lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Xiao Yang

    2017-12-01

    Full Text Available Glycine, the simplest amino acid in nature and one of the most abundant free amino acids in soil, is regarded as a model nutrient in organic nitrogen studies. To date, many studies have focused on the uptake, metabolism and distribution of organic nitrogen in plants, but few have investigated the nutritional performance of plants supplied with organic nitrogen. Lettuce (Lactuca sativa L., one of the most widely consumed leafy vegetables worldwide, is a significant source of antioxidants and bioactive compounds such as polyphenols, ascorbic acid and tocopherols. In this study, two lettuce cultivars, Shenxuan 1 and Lollo Rossa, were hydroponically cultured in media containing 4.5, 9, or 18 mM glycine or 9 mM nitrate (control for 4 weeks, and the levels of health-promoting compounds and antioxidant activity of the lettuce leaf extracts were evaluated. Glycine significantly reduced fresh weight compared to control lettuce, while 9 mM glycine significantly increased fresh weight compared to 4.5 or 18 mM glycine. Compared to controls, glycine (18 mM for Shenxuan 1; 9 mM for Lollo Rossa significantly increased the levels of most antioxidants (including total polyphenols, α-tocopherol and antioxidant activity, suggesting appropriate glycine supply promotes antioxidant accumulation and activity. Glycine induced most glycosylated quercetin derivatives and luteolin derivatives detected and decreased some phenolic acids compared to nitrate treatment. This study indicates exogenous glycine supplementation could be used strategically to promote the accumulation of health-promoting compounds and antioxidant activity of hydroponically grown lettuce, which could potentially improve human nutrition.

  17. Isolation, structure, and surfactant properties of polysaccharides from Ulva lactuca L. from South China Sea.

    Science.gov (United States)

    Tian, Hua; Yin, Xueqiong; Zeng, Qinghuan; Zhu, Li; Chen, Junhua

    2015-08-01

    Two polysaccharides (ULP1 and ULP2) were isolated through ultrasonic-assisted extraction from green seaweed Ulva lactuca L. which was collected from the South China Sea. The highest yield of 17.57% was obtained under the conditions of 2% NaOH, 90 °C, material/water mass ratio 1:80, liquid extraction 5h and subsequent ultrasound-assisted extraction 1h. The structure of ULPs were characterized with periodate oxidation followed by Smith degradation, (1)H NMR, (13)C NMR spectroscopy, FTIR, and GPC. The molecular weights of ULP1 and ULP2 were 189 kDa and 230 kDa, respectively. The structural characteristics of ULP1 and ULP2 were quite similar. They were composed of rhamnose, xylose, glucose, and glucuronic acid. The content of rhamnose, xylose, glucose, glucuronic acid, sulfate was 51.2%, 12.3%, 20.1%, 16.4%, 12.0% for ULP1, respectively, and 60.8%, 14.2%, 8.2%, 16.8%, 26.8%, respectively, for ULP2. Both ULP1 and ULP2 showed good surface activity. 5 mg/mL ULP1 (2.62×10(-2) mmol/L) decreased the water surface tension to 51.63 mN/m. The critical micellar concentration of ULP1 and ULP2 was 1.01 mg/mL (5.3×10(-3) mmol/L) and 1.14 mg/mL (5.0×10(-3) mmol/L), respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Protective effect of Ulva lactuca extract during hepatic cold preservation in rats.

    Science.gov (United States)

    Ferchichi, Henda; Bacha, Sarra; Kourda, Nadia; Melaouhia, Salma; Gaies, Emna; Lakhal, Mohamed; Klouz, Anis; Trabelsi, S; Salouage, Issam

    2016-04-01

    from the green seaweed Ulva lactuca to improve the conservation solution of organs against the hepatic effects of ischemia.

  19. Combined effects of dissolved humic acids and tourmaline on the accumulation of 2, 2', 4, 4', 5, 5'- hexabrominated diphenyl ether (BDE-153) in Lactuca sativa.

    Science.gov (United States)

    Wang, Cuiping; Ma, Chuanxin; Jia, Weili; Wang, Dong; Sun, Hongwen; Xing, Baoshan

    2017-12-01

    In order to investigate the effects of dissolved humic acid (DHA) and tourmaline on uptake of 2, 2', 4, 4', 5, 5'- hexabrominated diphenyl ether (BDE-153) by Lactuca sativa, different fractions of DHA, including DHA 1 and DHA 4 , as well as different doses of tourmaline were introduced into BDE-153 contaminated solutions for plant growth. The levels of BDE-153 in L. sativa tissues were positively correlated with the Fe levels (R 2  = 0.9264) in seedings of the treatments with different doses of tourmaline. However, when adding DHA 1 and DHA 4 into the system, the correlation coefficients (R 2 ) decreased to 0.6976 and 0.5451 from 0.9264, respectively. In contrast with the Fe contents, the presence of DHAs didn't affect the R 2 between the levels of BDE-153 and the lipid contents in plant tissues. Our results indicated that both DHA 1 and DHA 4 could severely alter the BDE-153 uptake by L. sativa through reducing the Fe uptake instead of the lipid contents. Additionally, DHA 4 exhibited much stronger abilities to alter the BDE-153 accumulation than DHA 1 . Transmission electron microscopy (TEM) observations indicated that either DHA 1 or tourmaline or co-treatment with DHA and tourmaline had no negative impact on L. sativa at the cellular level. The present study provides important information for the impacts of different fractions of DHA extracted from soil on the BDE-153 migration in plant systems. Moreover, we elucidated the importance of the iron in tourmaline for migration of the polybrominated diphenyl ethers (PBDEs) in plant systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Avaliação do efeito da peletização sobre o vigor de sementes de alface (Lactuca sativa L. Evaluation of the pelletization effect on lettuce seed vigor (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    H.M. Coraspe

    1993-12-01

    Full Text Available Sementes de alface (Lactuca sativa L. cv. Verônica, do tipo crespo, foram submetidas a testes de umidade, germinação, velocidade de germinação, envelhecimento acelerado, teste de frio, condutividade elétrica, e emergência. Os testes de laboratório não evidenciaram diferenças significativas da qualidade fisiológica entre sementes peletizadas e sem paletes, exceto o teste de envelhecimento acelerado. As correlações entre os testes de laboratório e a emergência em campo não foram significativas. A emergência em campo foi significativamente maior nas sementes peletizadas.Seeds of "Veronica", a crisphead lettuce cultivar (Lactuca sativa L., were submitted to laboratory tests of humidity, germination, velocity of germination, accelerated aging, cold, electrical conductivity and field emergence. Tests did not show any significant difference of the physiological quality between bare and pelleted seeds, except the accelerated aging. Correlations among laboratory tests and the field emergence were not significant. The field emergence was significantly higher from pelleted seeds than seeds without pellets.

  1. Carbon sp chains in graphene nanoholes

    DEFF Research Database (Denmark)

    Castelli, Ivano Eligio; Ferri, Nicola; Onida, Giovanni

    2012-01-01

    Nowadays sp carbon chains terminated by graphene or graphitic-like carbon are synthesized routinely in several nanotech labs. We propose an ab initio study of such carbon-only materials, by computing their structure and stability, as well as their electronic, vibrational and magnetic properties. We...

  2. Influence of synthetic surfactants on the uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Masakorala, Kanaji [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Turner, Andrew [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)], E-mail: aturner@plymouth.ac.uk; Brown, Murray T. [School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2008-12-15

    Uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca, has been studied in the presence of an anionic (sodium dodecyl sulphate, SDS), cationic (hexadecyltrimethylammonium bromide; HDTMA) and non-ionic (Triton X-100; TX) surfactant. Compared with the surfactant-free system, metal sorption was reduced in the presence of SDS or TX. Neither surfactant, however, had any measurable impact on cell membrane permeability, determined by leakage of dissolved free amino acids (DFAA), or on metal internalisation. We attribute these observations to the stabilisation of aqueous Cd and Pb by SDS and the shielding of otherwise amenable sorption sites by TX. Presence of HDTMA resulted in a reduction in the extent of both sorption and internalisation of all metals and a significant increase in the leakage of DFAA. Thus, by enhancing membrane permeability, HDTMA exerts the greatest influence on metal behaviour in the presence of U. lactuca. - Synthetic surfactants exert a significant impact on the uptake and internalisation of metals by a marine macroalga.

  3. An evaluation of the toxicity and bioaccumulation of thallium in the coastal marine environment using the macroalga, Ulva lactuca.

    Science.gov (United States)

    Turner, Andrew; Furniss, Oliver

    2012-12-01

    Thallium(I) has been added to cultures of the marine macroalga, Ulva lactuca, for a period of 48 h and the accumulation of the metal and its effects on the photochemical efficiency of photosystem II (PS II) measured. Thallium elicited a measurable toxic response above concentrations of 10 μg L⁻¹ in both coastal seawater (salinity 33) and estuarine water (salinity 20). The accumulation of Tl was defined by a linear relationship with aqueous Tl and accumulation factors of about 900 mL g⁻¹ in both media. Thallium accumulated by U. lactuca that was resistant to an EDTA extraction and, by operational definition, internalised, exceeded 90% in both cases. Accumulation and toxicity of Tl in the presence of a ∼10⁵-fold excess of its biogeochemical analogue, potassium, suggests that Tl has a high intrinsic phytotoxicity and that its mode of action involves permeation of the cell membrane as Tl⁺ through NaCl-KCl co-transporter sites rather than (or in addition to) transport through K⁺ ion channels. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Influence of synthetic surfactants on the uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca

    International Nuclear Information System (INIS)

    Masakorala, Kanaji; Turner, Andrew; Brown, Murray T.

    2008-01-01

    Uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca, has been studied in the presence of an anionic (sodium dodecyl sulphate, SDS), cationic (hexadecyltrimethylammonium bromide; HDTMA) and non-ionic (Triton X-100; TX) surfactant. Compared with the surfactant-free system, metal sorption was reduced in the presence of SDS or TX. Neither surfactant, however, had any measurable impact on cell membrane permeability, determined by leakage of dissolved free amino acids (DFAA), or on metal internalisation. We attribute these observations to the stabilisation of aqueous Cd and Pb by SDS and the shielding of otherwise amenable sorption sites by TX. Presence of HDTMA resulted in a reduction in the extent of both sorption and internalisation of all metals and a significant increase in the leakage of DFAA. Thus, by enhancing membrane permeability, HDTMA exerts the greatest influence on metal behaviour in the presence of U. lactuca. - Synthetic surfactants exert a significant impact on the uptake and internalisation of metals by a marine macroalga

  5. Metabolite profiling of sesquiterpene lactones from Lactuca species. Major latex components are novel oxalate and sulfate conjugates of lactucin and its derivatives.

    Science.gov (United States)

    Sessa, R A; Bennett, M H; Lewis, M J; Mansfield, J W; Beale, M H

    2000-09-01

    Wounding leaves or stems of Lactuca species releases a milky latex onto the plant surface. We have examined the constituents of latex from Lactuca sativa (lettuce) cv. Diana. The major components were shown to be novel 15-oxalyl and 8-sulfate conjugates of the guaianolide sesquiterpene lactones, lactucin, deoxylactucin, and lactucopicrin. The oxalates were unstable, reverting to the parent sesquiterpene lactone on hydrolysis. Oxalyl derivatives have been reported rarely from natural sources. The sulfates were stable and are the first reported sesquiterpene sulfates from plants. Unusual tannins based on 4-hydroxyphenylacetyl conjugates of glucose were also identified. Significant qualitative and quantitative variation was found in sesquiterpene lactone profiles in different lettuce varieties and in other Lactuca spp. The proportions of each conjugate in latex also changed depending on the stage of plant development. A similar profile was found in chicory, in which oxalyl conjugates were identified, but the 8-sulfate conjugates were notably absent. The presence of the constitutive sesquiterpene lactones was not correlated with resistance to pathogens but may have a significant bearing on the molecular basis of the bitter taste of lettuce and related species. The induced sesquiterpene lactone phytoalexin, lettucenin A, was found in the Lactuca spp. but not in chicory.

  6. Molecular aspects of the antagonistic interaction of smoke-derived butenolides on the germination process of Grand Rapids lettuce (Lactuca sativa) achenes

    Czech Academy of Sciences Publication Activity Database

    Soós, V.; Sebestyén, E.; Pošta, Martin; Kohout, Ladislav; Light, M. E.; van Staden, J.; Balázs, E.

    2012-01-01

    Roč. 196, č. 4 (2012), s. 1060-1073 ISSN 0028-646X Institutional research plan: CEZ:AV0Z40550506 Keywords : abscisic acid * fire * germination * karrikinolide * Lactuca sativa * smoke Subject RIV: CE - Biochemistry Impact factor: 6.736, year: 2012

  7. Effects of different drying conditions on the rehydration ratio and water holding capacity properties in three different species of algae Ulva lactuca, Codium vermilara and Codium tomentosum

    Directory of Open Access Journals (Sweden)

    Paulo Marques Nunes

    2014-06-01

    In this work, it was concluded that higher drying temperature conditions originate lower rehydration ratio and consequent lower water holding capacity possibly due to a higher physical damage in the algae tissues. It was also observed that both Codium species have higher values for these two parameters than Ulva lactuca, under the same rehydration conditions.

  8. LSGermOPA, a custom OPA of 384 EST-derived SNPs for high-throughput lettuce (Lactuca sativa L.) germplasm fingerprinting

    Science.gov (United States)

    We assessed the genetic diversity and population structure among 148 cultivated lettuce (Lactuca sativa L.) accessions using the high-throughput GoldenGate assay and 384 EST (Expressed Sequence Tag)-derived SNP (single nucleotide polymorphism) markers. A custom OPA (Oligo Pool All), LSGermOPA was fo...

  9. Involvement of S-nitrosothiols modulation by S-nitrosoglutathione reductase in defence responses of lettuce and wild Lactuca spp. to biotrophic mildews.

    Science.gov (United States)

    Tichá, Tereza; Sedlářová, Michaela; Činčalová, Lucie; Trojanová, Zuzana Drábková; Mieslerová, Barbora; Lebeda, Aleš; Luhová, Lenka; Petřivalský, Marek

    2018-02-07

    Resistant Lactuca spp. genotypes can efficiently modulate levels of S-nitrosothiols as reactive nitrogen species derived from nitric oxide in their defence mechanism against invading biotrophic pathogens including lettuce downy mildew. S-Nitrosylation belongs to principal signalling pathways of nitric oxide in plant development and stress responses. Protein S-nitrosylation is regulated by S-nitrosoglutathione reductase (GSNOR) as a key catabolic enzyme of S-nitrosoglutathione (GSNO), the major intracellular S-nitrosothiol. GSNOR expression, level and activity were studied in leaves of selected genotypes of lettuce (Lactuca sativa) and wild Lactuca spp. during interactions with biotrophic mildews, Bremia lactucae (lettuce downy mildew), Golovinomyces cichoracearum (lettuce powdery mildew) and non-pathogen Pseudoidium neolycopersici (tomato powdery mildew) during 168 h post inoculation (hpi). GSNOR expression was increased in all genotypes both in the early phase at 6 hpi and later phase at 72 hpi, with a high increase observed in L. sativa UCDM2 responses to all three pathogens. GSNOR protein also showed two-phase increase, with highest changes in L. virosa-B. lactucae and L. sativa cv. UCDM2-G. cichoracearum pathosystems, whereas P. neolycopersici induced GSNOR protein at 72 hpi in all genotypes. Similarly, a general pattern of modulated GSNOR activities in response to biotrophic mildews involves a two-phase increase at 6 and 72 hpi. Lettuce downy mildew infection caused GSNOR activity slightly increased only in resistant L. saligna and L. virosa genotypes; however, all genotypes showed increased GSNOR activity both at 6 and 72 hpi by lettuce powdery mildew. We observed GSNOR-mediated decrease of S-nitrosothiols as a general feature of Lactuca spp. response to mildew infection, which was also confirmed by immunohistochemical detection of GSNOR and GSNO in infected plant tissues. Our results demonstrate that GSNOR is differentially modulated in interactions of

  10. Electron mass stopping power in H2

    Science.gov (United States)

    Fursa, Dmitry V.; Zammit, Mark C.; Threlfall, Robert L.; Savage, Jeremy S.; Bray, Igor

    2017-08-01

    Calculations of electron mass stopping power (SP) of electrons in H2 have been performed using the convergent close-coupling method for incident electron energies up to 2000 eV. Convergence of the calculated SP has been established by increasing the size of the close-coupling expansion from 9 to 491 states. Good agreement was found with the SP measurements of Munoz et al. [Chem. Phys. Lett. 433, 253 (2007), 10.1016/j.cplett.2006.10.114].

  11. Revision of the family Carabodidae (Acari, Oribatida) V. Fourth part. Two new species of the genus Congocepheus from the Republic of Rwanda: Congocepheus rwandensis sp. n., and Congocepheus kayoveae sp. n.

    Science.gov (United States)

    Fernandez, Nestor; Theron, Pieter; Leiva, Sergio

    2016-01-01

    Two new species from Rwanda are described utilizing optical and scanning electron microscope observations: Congocepheus rwandensis sp. n. and Congocepheus kayoveae sp. n. are compared to Congocepheus taurus Balogh 1961.

  12. Productividad de lechuga Lactuca sativa en condiciones de macrotúnel en suelo Vitric haplustands

    Directory of Open Access Journals (Sweden)

    Pedro Velásquez

    2014-12-01

    Full Text Available La agricultura urbana hace parte importante en la producción de alimentos para una población cada día más creciente. En este contexto, el objetivo de esta investigación fue evaluar la productividad del cultivo de lechuga Lactuca sativa var. Batavia bajo condiciones de macrotúnel con tres niveles de fertilización. El ensayo se realizó en la localidad de San Felipe, Pasto, Nariño, en un suelo Vitric haplustands; se evaluaron dos tipos de ambientes (condiciones de macrotúnel y a campo abierto, con tres niveles de fertilización: alto 115; 69; 210 kg/ha (N, P2 O5, k2O, medio 69; 23; 150 kg/ha (N, P2 O5, k2O y bajo 46; 11,5; 90 kg/ha (N, P2 O5, k2O. El macrotúnel fue construido con arcos de bambú y una cubierta plástica para invernaderos. El ensayo se estableció en un diseño de bloques completos al azar con arreglo de franjas divididas. Las variables agronómicas evaluadas fueron: peso de cabeza (PC, porcentaje de materia seca (aérea y de raíz, diámetro de cabeza (DC, días a cosecha (DCO y rendimiento (R. Además, se realizó un análisis económico de presupuesto parcial. Los resultados mostraron que el cultivo de lechuga en ambiente de macrotúnel obtuvo en: PC=2,24kg/planta; DC=20,33 cm y DCO=74 días; valores que presentaron diferencias estadísticas significativas con respecto al ambiente campo abierto. A diferencia de lo anterior el porcentaje de materia seca aérea, no presentó diferencias significativas en ninguno de los tratamientos; situación similar aconteció con las dosis de fertilización alto, medio y bajo de (N, P, K y las interacciones de estas, con los dos ambientes evaluados. El análisis económico mostró que las mayores utilidades se obtuvieron en el ambiente de macrotúnel con 11278 pesos/m2y una rentabilidad de 507%.

  13. Protective effects of Lactuca sativa ethanolic extract on carbon tetrachloride induced oxidative damage in rats

    Directory of Open Access Journals (Sweden)

    Hefnawy Taha M. Hefnawy

    2013-08-01

    Full Text Available Objective: To study the protective effects of the ethanolic extract of lettuce (Lactuca sativa L. var. longifolia leaves against the toxicity caused by carbon tetrachloride (CCl4 in reproductive system of rats. Methods: Lettuce leaves were dried and extracted with ethanol (plant: solvent, 1:10, w/v. The extract was filtered and evaporated to yield dried lettuce extract. Animals were divided into seven groups and treated with CCl4 and different concentrations of lettuce extract. At the end of the experimental period, the animals were sacrificed and blood was collected and centrifuged for serum separation. Body weights, testis size, histopathology of testis and liver, catalase (CAT activity, superoxide dismutase (SOD activity, peroxidase (POD activity, reduced glutathione (GSH, glutathione peroxidase activity (GSH-Px, thiobarbituric acid reactive substances (TBARS, nitrite level, and serum hormones were determined. Results: Oxidative stress induced by CCl4 (2 mL/kg body weight in rat decreases the increase in body weight and relative testis weight. It also markedly increases the level of TBARS and nitrites along with corresponding decrease in reduced glutathione and various antioxidant enzymes in testis (i.e., CAT, POD, SOD and GSH-Px. Serum level of testosterone, luteinizing hormone and follicle stimulating hormone was decreased while estradiol and prolactin were increased during CCl 4 treatment. Histopathology of CCl4-treated rats indicated the partial degeneration of germ and leydig cells along with deformities in spermatogenesis. Supplementation of lettuce extract (100, 150, 200 mg/kg body weight orally once a week for 10 weeks results in decrease of TBARS and nitrite, while increase in antioxidant enzymes; CAT, POD, SOD, GSH-Px and GSH contents. Serum level of testosterone, luteinizing hormone, follicle stimulating hormone, estradiol, prolactin, histology, body weight and relative testis weight was also concomitantly restored to near normal

  14. Protective effects of Lactuca sativa ethanolic extract on carbon tetrachloride induced oxidative damage in rats

    Science.gov (United States)

    Hefnawy, Hefnawy Taha M.; Ramadan, Mohamed Fawzy

    2013-01-01

    Objective To study the protective effects of the ethanolic extract of lettuce (Lactuca sativa L. var. longifolia) leaves against the toxicity caused by carbon tetrachloride (CCl4) in reproductive system of rats. Methods Lettuce leaves were dried and extracted with ethanol (plant: solvent, 1:10, w/v). The extract was filtered and evaporated to yield dried lettuce extract. Animals were divided into seven groups and treated with CCl4 and different concentrations of lettuce extract. At the end of the experimental period, the animals were sacrificed and blood was collected and centrifuged for serum separation. Body weights, testis size, histopathology of testis and liver, catalase (CAT) activity, superoxide dismutase (SOD) activity, peroxidase (POD) activity, reduced glutathione (GSH), glutathione peroxidase activity (GSH-Px), thiobarbituric acid reactive substances (TBARS), nitrite level, and serum hormones were determined. Results Oxidative stress induced by CCl4 (2 mL/kg body weight) in rat decreases the increase in body weight and relative testis weight. It also markedly increases the level of TBARS and nitrites along with corresponding decrease in reduced glutathione and various antioxidant enzymes in testis (i.e., CAT, POD, SOD and GSH-Px). Serum level of testosterone, luteinizing hormone and follicle stimulating hormone was decreased while estradiol and prolactin were increased during CCl4 treatment. Histopathology of CCl4-treated rats indicated the partial degeneration of germ and leydig cells along with deformities in spermatogenesis. Supplementation of lettuce extract (100, 150, 200 mg/kg body weight orally) once a week for 10 weeks results in decrease of TBARS and nitrite, while increase in antioxidant enzymes; CAT, POD, SOD, GSH-Px and GSH contents. Serum level of testosterone, luteinizing hormone, follicle stimulating hormone, estradiol, prolactin, histology, body weight and relative testis weight was also concomitantly restored to near normal level by

  15. Qualidade física, microbiológica e parasitológica de alfaces (Lactuca sativa de diferentes sistemas de cultivo Physical, microbiological and parasitological quality of lettuce (Lactuca sativa from different growing processes

    Directory of Open Access Journals (Sweden)

    Ligia Regina R. de Santana

    2006-06-01

    Full Text Available A alface (Lactuca sativa é a hortaliça folhosa mais comercializada no Brasil. Seu baixo valor calórico a qualifica para diversas dietas, o que favorece o seu consumo sob a forma crua, possibilitando a ocorrência de enfermidades intestinais. O objetivo deste trabalho foi realizar uma avaliação física, microbiológica e parasitológica de amostras de alfaces, variedade crespa, provenientes dos sistemas de cultivo orgânico, tradicional e hidropônico, comercializadas nos principais supermercados da cidade de Salvador (BA, no período de setembro de 2003 a junho de 2004. As amostras do cultivo hidropônico apresentaram o menor peso total e da parte bio-comestível, diferindo significativamente (pThe lettuce (Lactuca sativa has economic importance to the people in Brazil. The aim of this study was to carry out a physical, microbiological and parasitological evaluations in the lettuce samples - crisp variety, according to organic, traditional and hydroponics growing processes, commercialized at the supermarkets of the City of Salvador, Bahia, Brazil, collected from September/2003 until June/2004. The hydroponics lettuce samples showed the lowest total and edible part weight; they were inserted into Extra rate quality standard, according to the current legislation, whereas the organic and traditional lettuce samples were inserted into First and Second rate quality standard, respectively. The lettuce samples, independently of the growing process, showed low hygienic conditions, indicated by the presence of parasites of animal or human origin, and high concentration of fecal coliforms; the organic lettuce samples showed the highest frequencies of enteroparasities and fecal coliforms concentration, followed by the traditional and hydroponics lettuce samples. Considering the obtained results, the importance of this kind of food in the transmission of enteroparasities is stressed, as well as the need of actions which improve the sanitary conditions

  16. Fuzzy SP-irresolute functions

    International Nuclear Information System (INIS)

    Abbas, S.E.

    2004-01-01

    In this paper, fuzzy SP-irresolute, fuzzy SP-irresolute open and fuzzy SP-irresolute closed functions between fuzzy topological spaces in Sostak sense are defined. Their properties and the relationships between these functions and other functions introduced previously are investigated. Next fuzzy SP-connectedness is introduced and studied with the help of r-fuzzy strongly preopen sets

  17. Heavy metals deposited in the culture of lettuce (Lactuca sativa L.) by the influence of vehicular traffic in Pernambuco, Brazil.

    Science.gov (United States)

    França, Fernanda C S S; Albuuerque, Adriana M A; Almeida, Amanda C; Silveira, Patrícia B; Filho, Crescêncio A; Hazin, Clovis A; Honorato, Eliane V

    2017-01-15

    Currently one of the main sources of atmospheric pollution identified in urban centers is derived from both industrial and motor vehicle emissions. These pollutants can be adsorbed to particulate matter which is present in the air or deposited in the soil and plants, eventually reaching the human food chain. In this context, the present study aimed to determine the concentration of metals such as Cu, Pb, Cd, Ni and Zn in two subspecies of Lactuca sativa L. and in the soil from were lettuce samples were collected. The results for the soil samples analyzed show a possible contamination by Pb with concentration values as high as 140mg.kg(-1), which are above the Brazilian standards defined by Resolution CONAMA 420/2009 (Brazilian Environmental Council). However, the values found in the lettuce itself reveal that it is still suitable for consumption. Copyright © 2016. Published by Elsevier Ltd.

  18. A link between lead and cadmium kinetic speciation in seawater and accumulation by the green alga Ulva lactuca

    International Nuclear Information System (INIS)

    Muse, J.O.; Carducci, C.N.; Stripeikis, J.D.; Tudino, M.B.; Fernandez, F.M.

    2006-01-01

    In this work, studies on the bioaccumulation of Cd and Pb by Ulva lactuca at different sites of Gulf San Jorge (Patagonia, Argentina) are presented. Higher values of bioaccumulated Cd were found in Punta Maqueda - a site believed to serve as a control - in comparison to those in Punta Borja, a place highly exposed to urban and industrial activities. Consequently; the labile fractions of Cd and Pb in seawater were determined with a flow injection-preconcentration manifold interfaced to a graphite furnace-atomic absorption spectrometer (FI-GFAAS). The results obtained by kinetic speciation showed that the variable that correctly explains heavy metals accumulation in the alga, is the labile metal fraction in seawater. We propose to use an enhancement ratio - on the basis of the kinetically labile metal fraction - for calculation of the metal accumulated by the alga relative to its environment. - Metal kinetic speciation can overcome CF limitations for the evaluation of marine pollution

  19. Agronomical response of lettuce (Lactuca sativa L., variety “Black Seed Simpson”, to Enerplant biostimulant aplication

    Directory of Open Access Journals (Sweden)

    Michel Baldoquin Hernandez

    2015-03-01

    Full Text Available The research was done at the school vegetable garden of Los Indios in the municipality of Rio Cauto, Granma, from March through April, 2014. The objective was to evaluate the agronomical response of the cultivation of the lettuce (Lactuca sativa. L variety “Black Seeded Simpson to the foliar application of three doses of Enerplant. The biostimulant was applied in the morning 7 days after transplantation. The doses used were 0.5 mL.ha-1, 1 mL.ha-1 and 1.5 mL.ha-1. The yield components were evaluated. The obtained data were statistically processed using the software package STASTISTICA 6.0 for Windows. Results showed that the three doses had a positive effect on the cultivation yield. Best results were obtained with the application of the 1.5 mL.ha-1 dose. The majority of the evaluated indicators significantly increased.

  20. A link between lead and cadmium kinetic speciation in seawater and accumulation by the green alga Ulva lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Muse, J.O. [Departamento de Quimica Analitica y Fisicoquimica, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires, Qulmica Analitica, 3er. Piso, Junin 956-1113, Buenos Aires (Argentina)]. E-mail: jmuse@ffyb.uba.ar; Carducci, C.N. [Departamento de Quimica Analitica y Fisicoquimica, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires, Qulmica Analitica, 3er. Piso, Junin 956-1113, Buenos Aires (Argentina); Stripeikis, J.D. [Departamento de Quimica Inorganica, Analitica y Quimica Fisica/INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, 3er. Piso, Pabellon 2, Ciudad Universitavia, Buenos Aires (Argentina); Tudino, M.B. [Departamento de Quimica Inorganica, Analitica y Quimica Fisica/INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, 3er. Piso, Pabellon 2, Ciudad Universitavia, Buenos Aires (Argentina); Fernandez, F.M. [Departamento de Quimica Inorganica, Analitica y Quimica Fisica/INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, 3er. Piso, Pabellon 2, Ciudad Universitavia, Buenos Aires (Argentina)

    2006-05-15

    In this work, studies on the bioaccumulation of Cd and Pb by Ulva lactuca at different sites of Gulf San Jorge (Patagonia, Argentina) are presented. Higher values of bioaccumulated Cd were found in Punta Maqueda - a site believed to serve as a control - in comparison to those in Punta Borja, a place highly exposed to urban and industrial activities. Consequently; the labile fractions of Cd and Pb in seawater were determined with a flow injection-preconcentration manifold interfaced to a graphite furnace-atomic absorption spectrometer (FI-GFAAS). The results obtained by kinetic speciation showed that the variable that correctly explains heavy metals accumulation in the alga, is the labile metal fraction in seawater. We propose to use an enhancement ratio - on the basis of the kinetically labile metal fraction - for calculation of the metal accumulated by the alga relative to its environment. - Metal kinetic speciation can overcome CF limitations for the evaluation of marine pollution.

  1. [Agrobacterium-mediated transformation of lettuce (Lactuca sativa L.) with vectors bearing genes of bacterial antigenes from Mycobacterium tuberculosis].

    Science.gov (United States)

    Marveeva, N A; Vasilenko, M Iu; Shakhovskiĭ, A M; Kuchuk, N V

    2009-01-01

    Transgenic plants of lettuce Lactuca sativa L. cv. Eralash, Sniezinka, Rubinovoje kruzevo with genes coding synthesis of tuberculosis antigenes have been obtained by Agrobacterium-mediated transformation. Cotyledons of in vitro seedlings were used as the initial material for transformation with plasmids pCB063 (genes ESAT6, nptII) and pCB064 (genes ESAT6:AG85B(-TMD), nptII). PCR-analysis has shown the presence both selective and target genes in all plants analyzed. At the same time, the RT-PCR has shown that both the presence and the absence of a transcription of gene ESAT6 at a stable transcription of a gene nptII is possible.

  2. Experimental determinations of soil copper toxicity to lettuce (Lactuca sativa) growth in highly different copper spiked and aged soils

    DEFF Research Database (Denmark)

    Christiansen, Karen Søgaard; Borggaard, Ole K.; Holm, Peter Engelund

    2015-01-01

    Accurate knowledge about factors and conditions determining copper (Cu) toxicity in soil is needed for predicting plant growth in various Cu-contaminated soils. Therefore, effects of Cu on growth (biomass production) of lettuce (Lactuca sativa) were tested on seven selected, very different soils...... of dissolved organic carbon [DOC] which together could explain 87 % of the pEC50(Cu2+) variation according to the simple equation: pEC50(Cu2+) = 0.98 × pH + 345 × [DOC] − 0.27. Other soil characteristics, including the base cation concentrations (Na+, K+, Ca2+, Mg2+), the cation exchange capacity at soil p......H (ECEC), and at pH 7 (CEC7), soil organic carbon, clay content, and electric conductivity as well as the distribution coefficient (Kd) calculated as the ratio between total soil Cu and water-extractable Cu did not correlate significantly with pEC50(Cu2+). Consequently, Cu toxicity, expressed...

  3. Influence of seaweed liquid fertilizer of ulva lactuca on the seed germination, growth, productivity of Abelmoschus esculentus (L.

    Directory of Open Access Journals (Sweden)

    Kaisarla Divya

    2015-12-01

    Full Text Available The present investigation is an attempt to study the influence of seaweed liquid fertiliger (SLF extracted from the marine green algae ulva lactuca on the growth parameters of Abelmoschus esculentus (l medikus. The seeds were soaked in different concentrations of SLF viz., 2.5%, 5%, 10%, 20% and control for 6h. The foliar spry was applied twice at four concentrations of seaweed extract. The maximum growth was recorded at 5% concentration viz., seed germination, shoot length, root length, no. of flowers, no. of fruits, fresh weight and dry weight when compare to control and remaining concentrations of seaweed extract. The seaweed extract are found effective in increasing the growth parameters.

  4. Fitotoxicidade e citogenotoxicidade da água e sedimento de córrego urbano em bioensaio com Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Luiz C. de A. Rodrigues

    2013-10-01

    Full Text Available Objetivou-se, com este trabalho, avaliar a influência espacial e temporal da fitotoxicidade e da citogenotoxicidade da água e do sedimento de córrego urbano quanto às características germinativas e de crescimento inicial de Lactuca sativa. Amostras de água e de sedimento foram coletadas em 5 pontos do Córrego do Pântano (Alfenas, Minas Gerais, no período de outubro de 2010 a julho de 2011 e as concentrações dos metais Cd, Pb e Zn foram quantificadas. Os ensaios de fitotoxicidade e de citogenotoxicidade foram realizados com as amostras de água e extratos aquosos dos sedimentos. Os parâmetros avaliados foram taxa de germinação, comprimento de raízes, biomassa fresca e seca, índice mitótico e a frequência de anormalidades cromossômicas. Constataram-se maiores concentrações de Cd e Pb nas amostras de água coletadas nos meses com a ocorrência de precipitações pluviométricas. Água e sedimento apresentaram efeito fitotóxico sobre germinação, biomassa fresca e seca de Lactuca sativa. O comprimento de raízes foi estimulado e apenas as amostras de água reduziram o índice mitótico. Evidenciou-se, também, variação temporal significativa relacionada com o regime pluviométrico apenas para o teste de fitotoxicidade.

  5. The Role of Carbon Concentrating Mechanisms in the Varied Response of the Green Macroalga, Ulva Lactuca, To Ocean Acidification

    Science.gov (United States)

    Scoma, S. R.; Kubler, J.; Nisumaa, A. M.

    2016-02-01

    The majority of fleshy macroalgae, across all groups, contain carbon-concentrating mechanisms (CCMs) that facilitate use of dissolved inorganic carbon. Rising atmospheric CO2 concentrations and the resulting shift in seawater carbonate chemistry (ocean acidification, OA) may have varying effects on algae depending on their mode of inorganic carbon concentration, if any, and its regulation. Energetic costs of carbon uptake mechanisms may change with rising pCO2 and that may explain the variability in effects of OA on growth and photosynthesis. We investigated the relative activity of CCMs in the green alga Ulva lactuca across a range of atmospheric CO2 concentrations (385-1200 μatm) spanning recent concentrations to the high end predictions for 2100 (IPCC). U. lactuca is a fast growing species with a well characterized, multistep CCM that uses HCO3- to saturate photosynthesis with inorganic carbon. To test for responses to OA, we cultured the alga for 21 days at various pCO2 concentrations. A pH drift experiment was then performed to determine the relative activity of the CCMs if present. The CCM of Ulva showed a potentially bimodal response with sustained activity of bicarbonate anion exchange proteins in some individuals with a declining efficiency of external carbonic anhydrase, as pCO2 increased. The growth rate was enhanced by intermediate pCO2 relative to recent and very high pCO2. The results indicate that the CCM of Ulva is regulated in response to ocean acidification, and there is substantial variation between individual responses. This concurs with the finding that growth increases in Ulva as pCO2 increases, but indicates an upper threshold of this benefit and potentially high variation within populations.

  6. [A STUDY OF THE ISOLATED BACTERIOPHAGE ΦAB-SP7 ADSORPTION ON THE CELL SURFACE OF THE AZOSPIRILLUM BRASILENSE SP7].

    Science.gov (United States)

    Guliy, O I; Karavaeva, O A; Velikov, V A; Sokolov, O I; Pavily, S A; Larionova, O S; Burov, A M; Ignatov, O V

    2016-01-01

    The bacteriophage ΦAb-Sp7 was isolated from the cells of the Azospirillum brasilense Sp7. The morphology, size of the gram-negative colonies, and range of lytic activity against other strains and species of the genus Azospirillum was tested. The isolated phage DNA was examined using electrophoretic and restriction analysis, and the size of the genome were established. The electron microscopy. resuIts show that the phage (capsid) has a strand-like form. The electron microscopy study of the bacteriophage ΦAb-Sp7 adsorption on the A. brasilense Sp7 bacterial surface was performed.

  7. Comparative allelopathic effects of Cryptocarya moschata and Ocotea odorifera aqueous extracts on Lactuca sativa - doi: 10.4025/actasciagron.v35i2.15758

    Directory of Open Access Journals (Sweden)

    Franciele Carla Prichoa

    2012-12-01

    Full Text Available The aim of this work was to compare the allelopathic effects of aqueous leaf extracts from Cryptocarya moschata and Ocotea odorifera on the seed germination and initial growth of Lactuca sativa (lettuce. The extracts were prepared by cold maceration, which was accomplished by adding distilled water to the dried plant material 1:10 (w v-1 and grinding. The treatment concentrations (0, 0.25, 0.5, 0.75 and 1% were obtained by dissolving the dried crude extract in distilled water. The allelopathic potential of the dried Ocotea odorifera and Cryptocarya moschata leaves on Lactuca sativa was observed through reduction of the percentage of seeds that germinated, the index of germination and the length of the roots as well as structural abnormalities in L. sativa seedlings. For both extracts, the extract concentration and allelopathic effect were highly correlated. However, the C. moschata extract had no effect on caulicle length at the different tested concentrations.

  8. ATIVIDADE ALELOPÁTICA DE Araucaria angustifolia (Bertol. Kuntze NA GERMINAÇÃO E CRESCIMENTO INICIAL DE Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Bruna Denardin da Silveira

    2014-01-01

    Full Text Available The present study aimed to evaluate the possible allelopathic activities effects from Araucaria angustifolia on Lactuca sativa germination and initial growth. For this trial, lettuce seeds were used and aqueous extract extracted from the leaves of araucaria, with concentrations of 10%, 7.5%, 5.0% and 2.5%. The effect of the - se four concentrations was compared with distilled water (concentration 0%. Based on the collected data, percentage of germination (G%, germination speed index (GSI, average germination time (t, seedlings length and dried mass were determined. Results showed that aqueous extract from araucaria leaves has an inhibitory property on germination, germination speed index and initial growth in Lactuca sativa.

  9. Seasonal changes in nutrient limitation and nitrate sources in the green macroalga Ulva lactuca at sites with and without green tides in a northeastern Pacific embayment.

    Science.gov (United States)

    Van Alstyne, Kathryn L

    2016-02-15

    In Penn Cove, ulvoid green algal mats occur annually. To examine seasonal variation in their causes, nitrogen and carbon were measured in Ulva lactuca in May, July, and September and stable nitrogen and oxygen isotope ratios were quantified in U. lactuca, Penn Cove seawater, upwelled water from Saratoga Passage, water near the Skagit River outflow, and effluents from wastewater treatment facilities. Ulvoid growth was nitrogen limited and the sources of nitrogen used by the algae changed during the growing season. Algal nitrogen concentrations were 0.85-4.55% and were highest in September and at sites where algae were abundant. Upwelled waters were the primary nitrogen source for the algae, but anthropogenic sources also contributed to algal growth towards the end of the growing season. This study suggests that small nitrogen inputs can result in crossing a "tipping point", causing the release of nutrient limitation and localized increases in algal growth. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Plant growth-promoting bacterium Acinetobacter calcoaceticus P23 increases the chlorophyll content of the monocot Lemna minor (duckweed) and the dicot Lactuca sativa (lettuce).

    Science.gov (United States)

    Suzuki, Wakako; Sugawara, Masayuki; Miwa, Kyoko; Morikawa, Masaaki

    2014-07-01

    Acinetobacter calcoaceticus P23 is a plant growth-promoting bacterium that was isolated from the surface of duckweed (Lemna aoukikusa). The bacterium was observed to colonize on the plant surfaces and increase the chlorophyll content of not only the monocotyledon Lemna minor but also the dicotyledon Lactuca sativa in a hydroponic culture. This effect on the Lactuca sativa was significant in nutrient-poor (×1/100 dilution of H2 medium) and not nutrient-rich (×1 or ×1/10 dilutions of H2 medium) conditions. Strain P23 has the potential to play a part in the future development of fertilizers and energy-saving hydroponic agricultural technologies. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  11. Carbon sp chains in graphene nanoholes

    Science.gov (United States)

    Castelli, Ivano E.; Ferri, Nicola; Onida, Giovanni; Manini, Nicola

    2012-03-01

    Nowadays sp carbon chains terminated by graphene or graphitic-like carbon are synthesized routinely in several nanotech labs. We propose an ab initio study of such carbon-only materials, by computing their structure and stability, as well as their electronic, vibrational and magnetic properties. We adopt a fair compromise of microscopic realism with a certain level of idealization in the model configurations, and predict a number of properties susceptible to comparison with experiment.

  12. A sp2+sp3 hybridized carbon allotrope transformed from AB stacking graphyne and THD-graphene

    Directory of Open Access Journals (Sweden)

    Yu Zhang

    2018-01-01

    Full Text Available New carbon allotropes can be designed by combining sp, sp2 and sp3 three hybridization states. And the hybridization states or coordination numbers of carbon atoms can be changed by applying high pressure on carbon materials. In this study, a common high pressure phase (named as TBBC transformed from AB-stacking graphyne or THD-graphene is predicted. Its kinetic stability is examined using finite displacement method. We find that the sp2 and sp3 hybridized carbon atoms behave different vibration features at high frequency region. Both graphene-like and diamond-like vibration peaks occurs. Phase transition energy barriers from both graphyne and THD-graphene to TBBC are estimated. Electronic structure calculations show that the TBBC is an indirect semiconductor with a bandgap of 0.66 eV. The ideal tensile strength of TBBC is high in [0001] and [11¯00] directions, but is weak along [12¯10] direction.

  13. A sp2+sp3 hybridized carbon allotrope transformed from AB stacking graphyne and THD-graphene

    Science.gov (United States)

    Zhang, Yu; Shang, Jiacheng; Fu, Weida; Zeng, Li; Tang, Tao; Cai, Yingxiang

    2018-01-01

    New carbon allotropes can be designed by combining sp, sp2 and sp3 three hybridization states. And the hybridization states or coordination numbers of carbon atoms can be changed by applying high pressure on carbon materials. In this study, a common high pressure phase (named as TBBC) transformed from AB-stacking graphyne or THD-graphene is predicted. Its kinetic stability is examined using finite displacement method. We find that the sp2 and sp3 hybridized carbon atoms behave different vibration features at high frequency region. Both graphene-like and diamond-like vibration peaks occurs. Phase transition energy barriers from both graphyne and THD-graphene to TBBC are estimated. Electronic structure calculations show that the TBBC is an indirect semiconductor with a bandgap of 0.66 eV. The ideal tensile strength of TBBC is high in [0001] and [1 1 ¯ 00 ] directions, but is weak along [1 2 ¯ 10 ] direction.

  14. Novas raças de Bremia lactucae, agente causador do míldio da alface, identificadas no estado de São Paulo New races of Bremia lactucae, causal agent of lettuce downy mildew, identified in São Paulo state, Brazil

    Directory of Open Access Journals (Sweden)

    Jean de O Souza

    2011-09-01

    Full Text Available O objetivo deste trabalho foi relatar o surgimento de raças de Bremia lactucae, agente causal do míldio nas principais regiões produtoras de alface do estado de São Paulo. O estudo foi realizado no Laboratório de Melhoramento Genético de Hortaliças do Departamento de Produção Vegetal da UNESP, Campus de Jaboticabal. No período de 2006 e 2007, foram coletados 36 isolados de B. lactucae de diferentes regiões produtoras de alface no estado. Para identificação das raças foram utilizadas as cultivares diferenciadoras conforme o código "Sextet". Foram identificadas três novas raças, SPBl:02, SPBl:03 e SPBl:04 com os referidos comportamentos do fungo: (63/31/19/00, (63/63/19/00 e (63/63/03/00. Os genes Dm-14, Dm-17, Dm-18, Dm-37 e Dm-38 conferem resistência a essas novas raças identificadas.The objective of this paper was to report new races of lettuce downy mildew causal agent Bremia lactucae in São Paulo State. The study was carried out in the laboratory of Crop Genetics in the Department of Crop Science at the college of Agricultural and Veterinary Sciences, Jaboticabal campus. A total of 36 isolates of B. lactucae was collected in different regions. The identification of races was based on compatibility reaction on the differential cultivars of the "Sextet". Three new races of B. lactucae, SPBl:02 (63/31/19/00, SPBl:03 (63/63/19/00 and SPBl:04 (63/63/03/00 were identified according to "Sextet" code. Genes Dm-14, Dm-17, Dm-18, Dm-37 and Dm-38 confer resistance to these new races identified.

  15. The Influenced of Lactobacillus plantarum Starter Addition and The Length Time of Fermentation Process on The Activity of Seaweed Antioxidant Ulva lactuca from Krakal Beach, Yogyakarta

    Science.gov (United States)

    Ambarsari, N. D.; Rushanti, I. R. P. A.; Setyaji, A.; Ningsih, T. R.; Nurhana, N.; Subekhi, I.; Dewi, E. N.

    2018-02-01

    Seaweed contains phenol compound functioning as antioxidant. Lactobacillus plantarum starter addition in a fermentation process was expected will increase the activity of antioxidant. The purpose of this research was to determine the influence of L. plantarum addition and the length of fermentation on the activity of antioxidant in U. lactuca. The experiment was conducted with factorial design. The first treatment consisted 2 different factors namely without L. plantarum addition and L. plantarum addition. While the second treatment were the different length fermentation time: 0, 12, 24, and 36 hours. Each treatment were done in thriplicate. The data was analyzed using ANOVA and BNJ test was applied if there any differences betweenthe treatments. The results showed that the fresh U. lactuca with L. plantarum addition for 36 hours fermentation had TPC BAL 9,83 CFU/ml, pH 4,26, phenol 231 ppm and antioxidant activity IC501375,12 ppm. Dried U. lactuca with L. plantarum addition that was fermentized for 36 hours had TPC BAL 9,10 CFU/ml, pH 4,75, phenol 166,24 ppm and antioxidant activity IC504070,32 ppm. The fresh U. lactuca with L. plantarum addition for 36 hours fermentation was the best treatment since the antioxidant activity is IC501375,12 ppm. Although the antioxidant activity was categorized as weak but it was still showed an increase compared to the result of antioxidant activity with maceration method using n-hexana dissolver which was 11213,76 ppm, ethyl acetate 9770,285 ppm, and ethanol extact 4921,79 ppm.

  16. Chemical and biological evaluation of the nutritive value of Algerian green seaweed Ulva lactuca using in vitro gas production technique fior ruminant animals

    OpenAIRE

    Zitouni, Hind; Arhab, Rabah; Boudry, Christelle; Bousseboua, Hacène; Beckers, Yves

    2014-01-01

    This study aimed to determine the nutritive value of seaweed Ulva lactuca collected from the Algerian coast by estimation of its chemical composition and fermentation characteristics, comparatively to vetch-oat hay (control), using in vitro gas production technique. Seaweed and control were incubated with rumen liquor taken from fistulated and non lactating cows. Gas production was recorded at: 2, 4, 6, 8, 12, 24, 48 and 72h. The in vitro rumen fermentation parameters were measured after 24h ...

  17. δ(15)N variation in Ulva lactuca as a proxy for anthropogenic nitrogen inputs in coastal areas of Gulf of Gaeta (Mediterranean Sea).

    Science.gov (United States)

    Orlandi, Lucia; Bentivoglio, Flavia; Carlino, Pasquale; Calizza, Edoardo; Rossi, David; Costantini, Maria Letizia; Rossi, Loreto

    2014-07-15

    We tested the capacity of Ulva lactuca to mark N sources across large marine areas by measuring variation in its δ(15)N at several sites in the Gulf of Gaeta. Comparisons were made with the macroalga Cystoseira amentacea. Variation of δ(15)N values was assessed also in the coastal waters off the Circeo Natural Park, where U. lactuca and C. amentacea were harvested, as these waters are barely influenced by human activities and were used as reference site. A small fragment from each frond was preserved before deployment in order to characterize the initial isotopic values. After 48 h of submersion, U. lactuca was more responsive than C. amentacea to environmental variation and δ(15)N enrichment in the Gulf of Gaeta was observed. The spatial distribution of δ(15)N enrichment indicated that different macro-areas in the Gulf were affected by N inputs from different origins. Comparison of the δ(15)N values of fragments taken from the same transplanted frond avoided bias arising from natural isotopic variability. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Cryptosporidium sp. in lizards

    Czech Academy of Sciences Publication Activity Database

    Koudela, Břetislav; Modrý, D.

    1998-01-01

    Roč. 45, č. 1 (1998), s. 8 ISSN 1066-5234. [ Cryptosporidium sp. in lazards. 01.01.1998-02.01.1998, Praha] R&D Projects: GA ČR GA508/95/0273; GA AV ČR IPP2020702 Subject RIV: fp - Other Medical Disciplines

  19. Produção de alface (Lactuca sativa L. sob diferentes doses de vermicomposto

    Directory of Open Access Journals (Sweden)

    M. S. Teodoro

    2016-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de diferentes dosagens de vermicomposto sobre a produção de alface, cultivar Baba de Verão. O ensaio foi conduzido em Latossolo Amarelo Distrófico de textura média fase caatinga litorânea, na Embrapa Meio-Norte, UEP – Parnaíba, de setembro a outubro de 2013. O delineamento experimental adotado foi o de blocos casualizados, com cinco tratamentos e quatro repetições.  Os tratamentos constituíram-se das dosagens de vermicomposto aplicadas na adubação das covas: 0 g/cova; 62,5 g/cova; 125 g/cova; 187,5 g/cova e 250 g/cova. As características avaliadas foram: Diâmetro da base (DB; Número de folhas (NF; Massa fresca da parte aérea (MFPA; Massa fresca da raiz (MFR; Massa seca da parte aérea (MSPA e Massa seca da raiz (MSR. Para todas as características avaliadas o vermicomposto de minhoca apresentou resultados aceitáveis, não havendo diferenças significativas para a maioria das características agronômicas estudadas. Os maiores pesos médios foram obtidos com a dosagem de 187,5 g/cova (40 t/ha. A biomassa fresca e seca da alface obtida nesta dosagem foram superiores em aproximadamente 50 e 49%, respectivamente, em relação à testemunha. O mesmo observa-se para a massa fresca e seca das raízes (25 e 24%, respectivamente, apesar de não diferirem estatisticamente entre os demais tratamentos. Apesar dos problemas relacionados ao pendoamento, a utilização do vermicomposto, permitiu a obtenção de alface, demonstrando que a adubação de plantio com este insumo orgânico pode ser considerada uma prática promissora na produção dessa hortaliça em sistemas orgânicos na região. Entretanto, é importante se adequar a época de cultivo, ou então, trabalhar com cultivares adaptadas para as condições edafoclimáticas da região.  Production of lettuce (Lactuca sativa L. under different doses of worm compostAbstract: Different dosages of fertilization on the production of

  20. Truncated recombinant human SP-D attenuates emphysema and type II cell changes in SP-D deficient mice

    Directory of Open Access Journals (Sweden)

    Mühlfeld Christian

    2007-10-01

    Full Text Available Abstract Background Surfactant protein D (SP-D deficient mice develop emphysema-like pathology associated with focal accumulations of foamy alveolar macrophages, an excess of surfactant phospholipids in the alveolar space and both hypertrophy and hyperplasia of alveolar type II cells. These findings are associated with a chronic inflammatory state. Treatment of SP-D deficient mice with a truncated recombinant fragment of human SP-D (rfhSP-D has been shown to decrease the lipidosis and alveolar macrophage accumulation as well as production of proinflammatory chemokines. The aim of this study was to investigate if rfhSP-D treatment reduces the structural abnormalities in parenchymal architecture and type II cells characteristic of SP-D deficiency. Methods SP-D knock-out mice, aged 3 weeks, 6 weeks and 9 weeks were treated with rfhSP-D for 9, 6 and 3 weeks, respectively. All mice were sacrificed at age 12 weeks and compared to both PBS treated SP-D deficient and wild-type groups. Lung structure was quantified by design-based stereology at the light and electron microscopic level. Emphasis was put on quantification of emphysema, type II cell changes and intracellular surfactant. Data were analysed with two sided non-parametric Mann-Whitney U-test. Main Results After 3 weeks of treatment, alveolar number was higher and mean alveolar size was smaller compared to saline-treated SP-D knock-out controls. There was no significant difference concerning these indices of pulmonary emphysema within rfhSP-D treated groups. Type II cell number and size were smaller as a consequence of treatment. The total volume of lamellar bodies per type II cell and per lung was smaller after 6 weeks of treatment. Conclusion Treatment of SP-D deficient mice with rfhSP-D leads to a reduction in the degree of emphysema and a correction of type II cell hyperplasia and hypertrophy. This supports the concept that rfhSP-D might become a therapeutic option in diseases that are

  1. Truncated recombinant human SP-D attenuates emphysema and type II cell changes in SP-D deficient mice.

    Science.gov (United States)

    Knudsen, Lars; Ochs, Matthias; Mackay, Rosemarie; Townsend, Paul; Deb, Roona; Mühlfeld, Christian; Richter, Joachim; Gilbert, Fabian; Hawgood, Samuel; Reid, Kenneth; Clark, Howard

    2007-10-03

    Surfactant protein D (SP-D) deficient mice develop emphysema-like pathology associated with focal accumulations of foamy alveolar macrophages, an excess of surfactant phospholipids in the alveolar space and both hypertrophy and hyperplasia of alveolar type II cells. These findings are associated with a chronic inflammatory state. Treatment of SP-D deficient mice with a truncated recombinant fragment of human SP-D (rfhSP-D) has been shown to decrease the lipidosis and alveolar macrophage accumulation as well as production of proinflammatory chemokines. The aim of this study was to investigate if rfhSP-D treatment reduces the structural abnormalities in parenchymal architecture and type II cells characteristic of SP-D deficiency. SP-D knock-out mice, aged 3 weeks, 6 weeks and 9 weeks were treated with rfhSP-D for 9, 6 and 3 weeks, respectively. All mice were sacrificed at age 12 weeks and compared to both PBS treated SP-D deficient and wild-type groups. Lung structure was quantified by design-based stereology at the light and electron microscopic level. Emphasis was put on quantification of emphysema, type II cell changes and intracellular surfactant. Data were analysed with two sided non-parametric Mann-Whitney U-test. After 3 weeks of treatment, alveolar number was higher and mean alveolar size was smaller compared to saline-treated SP-D knock-out controls. There was no significant difference concerning these indices of pulmonary emphysema within rfhSP-D treated groups. Type II cell number and size were smaller as a consequence of treatment. The total volume of lamellar bodies per type II cell and per lung was smaller after 6 weeks of treatment. Treatment of SP-D deficient mice with rfhSP-D leads to a reduction in the degree of emphysema and a correction of type II cell hyperplasia and hypertrophy. This supports the concept that rfhSP-D might become a therapeutic option in diseases that are characterized by decreased SP-D levels in the lung.

  2. Photosynthetic Electron Transport Involved in PxcA-Dependent Proton Extrusion in Synechocystis sp. Strain PCC6803: Effect of pxcA Inactivation on CO2, HCO3−, and NO3− Uptake

    OpenAIRE

    Sonoda, Masatoshi; Katoh, Hirokazu; Vermaas, Wim; Schmetterer, George; Ogawa, Teruo

    1998-01-01

    The product of pxcA (formerly known as cotA) is involved in light-induced Na+-dependent proton extrusion. In the presence of 2,5-dimethyl-p-benzoquinone, net proton extrusion by Synechocystis sp. strain PCC6803 ceased after 1 min of illumination and a postillumination influx of protons was observed, suggesting that the PxcA-dependent, light-dependent proton extrusion equilibrates with a light-independent influx of protons. A photosystem I (PS I) deletion mutant extruded a large number of prot...

  3. Tsukamurella inchonensis sp. nov.

    Science.gov (United States)

    Yassin, A F; Rainey, F A; Brzezinka, H; Burghardt, J; Lee, H J; Schaal, K P

    1995-07-01

    Chemotaxonomic and genomic 16S ribosomal DNA sequence analyses of two isolates obtained from two different clinical materials clearly delineated a new species of the genus Tsukamurella. This new species can be identified by its 16S ribosomal DNA similarity values, as well as its physiological characteristics. The name Tsukamurella inchonensis sp. nov. is proposed for these isolates, which are represented by strain IMMIB D-771T (= DSM 44067T) (T = type strain). This strain exhibits only 45% DNA relatedness to Tsukamurella paurometabola.

  4. SP-100 surety evaluation

    International Nuclear Information System (INIS)

    1985-06-01

    This report describes surety evaluations conducted during GFY 1985 in support of the General Electric design for a Space Nuclear Power System - SP-100. Those surety evaluations address both safety and safeguards requirements, which are derived from OSNP-1 and supporting documents. The report includes results of neutronics (criticality) calculations performed by Los Alamos. The results have been benchmarked against independent calculations performed by General Electric with different codes. These comparisons show close agreement, and are summarized. Los Alamos has also provided specifications of explosion and fire environments, which have been used in evaluation of the GE SP-100 concept. Following the summary of key results, surety requirements are given and recommendations toward specification of requirements for later SP-100 project phases are presented. A conceptual design summary is presented. To establish a comprehensive background for surety evaluations, a reference mission profile and potential accidents for each phase of the mission are identified. The main body of the report addresses surety of the General Electric Thermoelectric Conversion design. GE has also developed a Stirling Engine concept, and performed comprehensive surety evaluations for it. These evaluations are reported

  5. Application of Ulva lactuca and Systoceira stricta algae-based activated carbons to hazardous cationic dyes removal from industrial effluents.

    Science.gov (United States)

    Salima, Attouti; Benaouda, Bestani; Noureddine, Benderdouche; Duclaux, Laurent

    2013-06-15

    Marine algae Ulva lactuca (ULV-AC) and Systoceira stricta (SYS-AC) based activated carbons were investigated as potential adsorbents for the removal of hazardous cationic dyes. Both algae were surface oxidised by phosphoric acid for 2 and subsequently air activated at 600 °C for 3 h. Dyes adsorption parameters such as solution pH, contact time, carbon dosage, temperature and ionic strength were measured in batch experiments. Adsorption capacities of 400 and 526 mg/g for Malachite green and Safranine O by the SYS-AC and ULV-AC respectively were significantly enhanced by the chemical treatments. Model equations such as Langmuir, Freundlich and Temkin isotherms were used to analyse the adsorption equilibrium data and the best fits to the experimental data were provided by the first two isotherm models. BET, FT-IR, iodine number and methylene blue index determination were also performed to characterize the adsorbents. To describe the adsorption mechanism, kinetic models such as pseudo-second-order and the intra particle diffusion were applied. Thermodynamic analysis of the adsorption processes of both dyes confirms their spontaneity and endothermicity. Increasing solution ionic strength increased significantly the adsorption of Safranine O. This study shows that surface modified algae can be an alternative to the commercially available adsorbents for dyes removal from liquid effluents. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Beneficial Phytochemicals with Anti-Tumor Potential Revealed through Metabolic Profiling of New Red Pigmented Lettuces (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Xiao-Xiao Qin

    2018-04-01

    Full Text Available The present study aimed to compare polyphenols among red lettuce cultivars and identify suitable cultivars for the development and utilization of healthy vegetables. Polyphenols, mineral elements, and antioxidant activity were analyzed in the leaves of six red pigmented lettuce (Lactuca sativa L. cultivars; thereafter, we assessed the anti-tumor effects of cultivar B-2, which displayed the highest antioxidant activity. Quadrupole–Orbitrap mass spectrometry analysis revealed four classes of polyphenols in these cultivars. The composition and contents of these metabolites varied significantly among cultivars and primarily depended on leaf color. The B-2 cultivar had the highest antioxidant potential than others because it contained the highest levels of polyphenols, especially anthocyanin, flavone, and phenolic acid; furthermore, this cultivar displayed anti-tumor effects against the human lung adenocarcinoma cell line A549, human hepatoma cell line Bel7402, human cancer colorectal adenoma cell line HCT-8, and HT-29 human colon cancer cell line. Hence, the new red-leaf lettuce cultivar B-2 has a distinct metabolite profile, with high potential for development and utilization of natural phytochemical and mineral resources in lettuces and can be used as a nutrient-dense food product.

  7. Accumulation of ixerin F and activities of some terpenoid bisynthetic enzymes in a cell suspension culture of Lactuca virosa L.

    Directory of Open Access Journals (Sweden)

    Anna Stojakowska

    2014-01-01

    Full Text Available A cell suspension culture of Lactuca virosa L. (Asteraceae, tribe Lactuceae is capable of synthesizing sesquiterpene lactones of which ixerin F is the main compound. The culture was characterized on growth (by dissimilation rates, on ixerin F accumulation (by RP-HPLC and on some enzyme activities involved in early steps of terpenoid biosynthesis. Acetoacetyl-coenzyme A thiolase (AACT, E.C. 2.3.1.9 and 3S-hydroxy-3-methylglutaryl-coenzyme A synthase (HMGS, E.C. 4.13.5 activities of the cells were assayed spectrophotometrically. HMGS activity increased during the culture period and reached a maximum during the stationary phase (190 pkat/mg protein, while AACT showed relatively high level of activity throughout the growth cycle, with transient decrease at the logarithmic growth phase and the beginning of stationary phase. Ixerin F accumulated inside the cells and the maximum concentration of 0.08% (on dry weight basis was found in the early stationary phase of the growth cycle of the culture.

  8. Validation of a Method for Cylindrospermopsin Determination in Vegetables: Application to Real Samples Such as Lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Ana I. Prieto

    2018-02-01

    Full Text Available Reports on the occurrence of the cyanobacterial toxin cylindrospermopsin (CYN have increased worldwide because of CYN toxic effects in humans and animals. If contaminated waters are used for plant irrigation, these could represent a possible CYN exposure route for humans. For the first time, a method employing solid phase extraction and quantification by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS of CYN was optimized in vegetables matrices such as lettuce (Lactuca sativa. The validated method showed a linear range, from 5 to 500 ng CYN g−1 of fresh weight (f.w., and detection and quantitation limits (LOD and LOQ of 0.22 and 0.42 ng CYN g−1 f.w., respectively. The mean recoveries ranged between 85 and 104%, and the intermediate precision from 12.7 to 14.7%. The method showed to be robust for the three different variables tested. Moreover, it was successfully applied to quantify CYN in edible lettuce leaves exposed to CYN-contaminated water (10 µg L−1, showing that the tolerable daily intake (TDI in the case of CYN could be exceeded in elderly high consumers. The validated method showed good results in terms of sensitivity, precision, accuracy, and robustness for CYN determination in leaf vegetables such as lettuce. More studies are needed in order to prevent the risks associated with the consumption of CYN-contaminated vegetables.

  9. Preliminary studies on growth and fresh weight of lettuce (Lactuca sativa) as affected by clay pot irrigation and spacing.

    Science.gov (United States)

    Abubakari, Abdul-Halim; Nyarko, George; Maalinyuur, Sheila

    2011-07-15

    An experiment (Completely Randomized Design) was set up to determine the effects of Clay Pot Sub-surface Irrigation (CPSI) and spacing on the growth and fresh weight of lettuce (Lactuca sativa). The treatments were: CPSI with spacing; 15 x 15 cm, 20 x 20 cm and 30 x 30 cm. Control treatments were Watering Can Irrigation (WCI) with the same spacing as above. Treatments were replicated three times given a total of 18 experimental units. Eighteen large enamel basins of 50/20 cm (diameter/height) were filled with good topsoil and a clay pot buried neck deep in each of the basins. Seedlings were planted in all the eighteen basins. Five Hundred mL of wastewater was applied daily to plants in each container having either clay pot or watering can treatment. Plant height increased from 2.50 to 4.25 cm within 6 Weeks after Transplanting (WAT) under CPSI and only increased from 2.14 to 2.99 cm under WCI. The CPSI also supported better leave growth and fresh weight. The fresh weight of lettuce increased almost two fold under 15 x 15 cm spacing compared to 20 x 20 and 30 x 30 cm.

  10. Effects of microcystin-LR, linear alkylbenzene sulfonate and their mixture on lettuce (Lactuca sativa L.) seeds and seedlings.

    Science.gov (United States)

    Wang, Zhi; Xiao, Bangding; Song, Lirong; Wu, Xingqiang; Zhang, Junqian; Wang, Chunbo

    2011-06-01

    Microcystin-LR (MCLR) and linear alkylbenzene sulfonate (LAS) are present widely in aquatic and terrestrial ecosystems, but their combined ecotoxicological risk is unknown. This study investigated the toxic effects of MCLR, LAS and their mixture on lettuce (Lactuca sativa L.) and evaluated MCLR accumulation level in lettuce with or without LAS. The changes in seed germination and shoot/root growth, responses of the antioxidative defense system, and the accumulation of MCLR in lettuce were tested to evaluate the single and combined toxic effect of MCLR and LAS in well-controlled conditions. The results showed that seedling growth (except for root elongation and leaf weight) was more sensitive to toxicant exposure than seed germination. For seedling leaves, lipid peroxidation was not observed when the antioxidative defense system (including superoxide dismutase, catalase and glutathione) was activated to relieve the adverse effects of oxidative stress via different pathways. Our results also confirmed that the interaction between MCLR and LAS was synergistic. Both toxicants in combination not only significantly inhibited seedling growth, but also increased the activities of superoxide dismutase and catalase, as well as the contents of glutathione. Furthermore, LAS dramatically enhanced the accumulation of MCLR in the plant, thus leading to a reduction in quality and yield and posing greater potential risk to humans via consumption of these edible plants.

  11. Role of manganese in low-pH-induced root hair formation in Lactuca sativa cv. Grand Rapids seedlings.

    Science.gov (United States)

    Konno, Masae; Ooishi, Machiko; Inoue, Yasunori

    2003-08-01

    Root hair formation is induced by low pH in lettuce ( Lactuca sativa L. cv. Grand Rapids) seedlings cultured in mineral medium. The role of mineral concentrations in this phenomenon was investigated, especially for manganese. When lettuce seedlings were cultured in media that were deficient in calcium (Ca), manganese (Mn), boron (B) or molybdenum (Mo), morphological changes were induced in roots. Deficiency of other nutrients had little effect on root hair formation. Ca or B deficiency inhibited the growth of the main root and the formation of root hairs, regardless of pH. Mn or Mo deficiency increased root hair formation at pH 6 and suppressed main root growth slightly. In contrast, increasing the Mn concentration suppressed low-pH-induced root hair formation. The Mn content of roots grown at pH 4 was only about 15% of that at pH 6. In contrast, the Mo content of roots grown at low pH was about six times that of roots grown at neutral pH. These results suggest that root hair formation induced by low pH is at least partly mediated by decreased Mn uptake in root cells.

  12. Effect of extraction procedures on structural, thermal and antioxidant properties of ulvan from Ulva lactuca collected in Monastir coast.

    Science.gov (United States)

    Yaich, Hela; Amira, Amal Ben; Abbes, Fatma; Bouaziz, Mohamed; Besbes, Souhail; Richel, Aurore; Blecker, Christophe; Attia, Hamadi; Garna, Haikel

    2017-12-01

    The present work aims to evaluate the effect of an acid extraction as well as a combined enzymatic-chemical extraction on structural, thermal and antioxidant properties of the sulphated polysaccharide 'ulvan' from the green seaweed Ulva lactuca. Structural characterization by FTIR and NMR spectroscopies showed the typical peaks of ulvan, namely, uronic acids, rhamnose and sulphate. FTIR analysis revealed that the extraction procedures were able to maintain ulvan structure. Despite differences in the extraction procedures, 13 C NMR spectra were globally similar, proving a comparable chemical structure of ulvans. A major difference has been observed in signal intensity which reflected the resonance of glucose or xylose. Thermal characterization proved that ulvans were thermally stable until approximately 180°C. Antioxidant properties of ulvans were evaluated in vitro through different antioxidant assays. Ulvan, which is extracted at pH 1.5 and 90°C, exhibited the greatest scavenging activity (IC 50 =13.56μg/ml) towards DPPH radical. Result indicated that Mw has influenced inhibitory effect on DPPH radical of ulvan. The current study revealed also a high correlation between sulphate contents of ulvans and their reducing power (R 2 =-0.89) and their metal scavenging activity (R 2 =0.97). Overall, ulvans have peculiar structural, thermal and antioxidant properties which promote their use in food or pharmaceutical products as natural ingredient. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. USO DE SUBSTRATOS ALTERNATIVOS PARA A PRODUÇÃO DE MUDAS DE ALFACE (LACTUCA SATIVA L.

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    Emanuele Baifus Manke

    2017-01-01

    Full Text Available O objetivo desse trabalho foi avaliar o efeito de diferentes substratos alternativos na produção de mudas de alface (Lactuca sativa L.. No experimento foram avaliados seis diferentes substratos. As variáveis avaliadas foram: número de folhas, comprimento de raiz, altura da muda, massa fresca de parte aérea, massa seca de parte aérea, massa fresca do sistema radicular e massa seca do sistema radicular. Os tratamentos T2: (75% Casca de Arroz Carbonizada + 25% Composto Orgânico Ecocitrus e T3: (50% Casca de Arroz Carbonizada + 50% Composto Orgânico Ecocitrus permitiram a obtenção de mudas de alface com boas respostas agronômicas, construindo-se uma opção viável na redução do custo para a produção de mudas de alface para a agricultura familiar.

  14. Toxic effects of copper-based nanoparticles or compounds to lettuce (Lactuca sativa) and alfalfa (Medicago sativa).

    Science.gov (United States)

    Hong, Jie; Rico, Cyren M; Zhao, Lijuan; Adeleye, Adeyemi S; Keller, Arturo A; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2015-01-01

    The increased production and use of nanoparticles (NPs) has generated concerns about their impact on living organisms. In this study, nCu, bulk Cu, nCuO, bulk CuO, Cu(OH)2 (CuPRO 2005, Kocide 3000), and CuCl2 were exposed for 15 days to 10 days-old hydroponically grown lettuce (Lactuca sativa) and alfalfa (Medicago sativa). Each compound was applied at 0, 5, 10, and 20 mg L(-1). At harvest, we measured the size of the plants and determined the concentration of Cu, macro and microelements by using ICP-OES. Catalase and ascorbate peroxidase activity was also determined. Results showed that all Cu NPs/compounds reduced the root length by 49% in both plant species. All Cu NPs/compounds increased Cu, P, and S (>100%, >50%, and >20%, respectively) in alfalfa shoots and decreased P and Fe in lettuce shoot (>50% and >50%, respectively, excluding Fe in CuCl2 treatment). Biochemical assays showed reduced catalase activity in alfalfa (root and shoot) and increased ascorbate peroxidase activity in roots of both plant species. Results suggest that Cu NPs/compounds not only reduced the size of the plants but altered nutrient content and enzyme activity in both plant species.

  15. Allelopathic evaluation of ethanol extracts of Copaifera sabulicola on the initial development of Lactuca sativa, Lycopersicum esculentum, and Zea mays

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    Manoel Viana Linhares Neto

    2014-05-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2014v27n3p23 This paper aimed to evaluate the allelopathic potential of ethanol extracts from stem and leaves of Copaifera sabulicola on seed germination and seedling growth of Lactuca sativa and Lycopersicum esculentum, as well as to evaluate the allelopathic effect of these extracts on seedling germination and growth of Zea mays, through bioassays under laboratory conditions. The extracts were tested at the concentrations 0, 250, 500, and 1,000 mg.L-1. We evaluated the germination percentage, germination average speed, germination speed index, and seedling average length. All parameters underwent variance analysis, and the mean values were compared by means of Scott-Knott test (p ≤ 0.05. We found out that, in L. sativa, the extract from stem promoted significant stimuli on germination percentage and root growth, while the extract from leaves only stimulated root growth. In L. esculentum, the extract from stem promoted significant stimulus on hypocotyl and root growth, in turn, the extract from leaves stimulated only root growth. In Z. mays, both extracts significantly inhibited germination. Therefore, we found out the allelopathic potential of ethanol extracts of C. sabulicola on L. sativa and L. esculentum, as well as inhibitory allelopathic effect on Z. mays.

  16. Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Zijing Chen

    2018-01-01

    Full Text Available Lettuce (Lactuca sativa L. is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce.

  17. Physiological Mechanisms Only Tell Half Story: Multiple Biological Processes are involved in Regulating Freezing Tolerance of Imbibed Lactuca sativa Seeds.

    Science.gov (United States)

    Jaganathan, Ganesh K; Han, Yingying; Li, Weijie; Song, Danping; Song, Xiaoyan; Shen, Mengqi; Zhou, Qiang; Zhang, Chenxue; Liu, Baolin

    2017-03-13

    The physiological mechanisms by which imbibed seeds survive freezing temperatures in their natural environment have been categorized as freezing avoidance by supercooling and freezing tolerance by extracellular freeze-desiccation, but the biochemical and molecular mechanisms conferring seed freezing tolerance is unexplored. In this study, using imbibed Lactuca sativa seeds we show that fast cooled seeds (60 °C h -1 ) suffered significantly higher membrane damage at temperature between -20 °C and -10 °C than slow cooled (3 °Ch -1 ) seeds (P  0.05). However, both SOD activity and accumulation of free proline were induced significantly after slow cooling to -20 °C compared with fast cooling. RNA-seq demonstrated that multiple pathways were differentially regulated between slow and fast cooling. Real-time verification of some differentially expressed genes (DEGs) revealed that fast cooling caused mRNA level changes of plant hormone and ubiquitionation pathways at higher sub-zero temperature, whilst slow cooling caused mRNA level change of those pathways at lower sub-zero ttemperatures. Thus, we conclude that imbibed seed tolerate low temperature not only by physiological mechanisms but also by biochemical and molecular changes.

  18. Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.)

    Science.gov (United States)

    Chen, Zijing; Han, Yingyan; Ning, Kang; Ding, Yunyu; Zhao, Wensheng; Yan, Shuangshuang; Luo, Chen; Jiang, Xiaotang; Ge, Danfeng; Liu, Renyi; Wang, Qian; Zhang, Xiaolan

    2018-01-01

    Lettuce (Lactuca sativa L.) is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT) gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce. PMID:29403510

  19. Evaluation of the toxic potential of coffee wastewater on seeds, roots and meristematic cells of Lactuca sativa L.

    Science.gov (United States)

    Aguiar, Luara Louzada; Andrade-Vieira, Larissa Fonseca; de Oliveira David, José Augusto

    2016-11-01

    Coffee wastewater (CWW) is an effluent produced through wet processing of coffee containing high concentration of organic matter, nutrients, salts and also agrochemicals. It is released directly into the argillaceous soil or into decantation tanks for later disposal into soils, by fertigation, subsurface infiltration or superficial draining. However, this practice is not followed by the monitoring the toxicity potential of this effluent. In this sense, the present work aimed to evaluate the phytotoxic, cytogenotoxic and mutagenic potential of CWW on seed germination, root elongation and cell cycle alterations in the plant model Lactuca sativa L. The effluent (CWW) collected was diluted in distilled water into six concentrations solutions (1.25%, 1.66%, 2.5%, 5.0%, 10%, 20%). A solution of raw CWW (100%) was also applied. Distilled water was used as negative control), and the DNA alkylating agent, metilmetano sulfonate (4×10(-4)M) as positive control. Physico-chemical parameters of the CWW was accessed and it was found that the effluent contained total phenols and inorganic matter in amounts within the limits established by the National Environment Council (CONAMA). Nevertheless, the biologicals assays performed demonstrated the phytotoxicity and cytogenotoxicty of CWW. Seed germination was totally inhibited after exposure of raw CWW. In addition, a decrease in seed germination speed as well as in root growth dose-dependently manner was noticed. Moreover, nuclear and chromosomal alterations were observed in the cell cycle, mostly arising from aneugenic action. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Anti-inflammatory and antioxidant activity of polyphenolic extracts from Lactuca sativa (var. Maravilla de Verano) under different farming methods.

    Science.gov (United States)

    Adesso, Simona; Pepe, Giacomo; Sommella, Eduardo; Manfra, Michele; Scopa, Antonio; Sofo, Adriano; Tenore, Gian Carlo; Russo, Mariateresa; Di Gaudio, Francesca; Autore, Giuseppina; Campiglia, Pietro; Marzocco, Stefania

    2016-09-01

    Besides their nutritional value, vegetables are a source of health-promoting compounds, such as polyphenols, and their content can be influenced by the particular farming method. In this study polyphenolic extracts from Lactuca sativa (var. Maravilla de verano) plants cultivated with different farming methods were chemically characterised and tested in vitro and ex vivo inflammation models. The tested extacts (250-2.5 µg mL(-1) ) were able to reduce both the inflammatory and oxidative stress in LPS-stimulated J774A.1 murine monocyte macrophage cells, by lowering the release of nitric oxide (NO) and reactive oxygen species (ROS) and promoting nuclear translocation of nuclear factor (erythroid-derived 2)-like 2; (Nrf2) and nuclear factor-κB (NF-κB). In this regard, quantitative profiles revealed different amounts of polyphenols, in particular quercetin levels were higher in plants under mineral fertilised treatment. Those extract showed an enhanced anti-inflammatory and antioxidant activity. Our data showed the anti-inflammatory and antioxidant potential of Maravilla de Verano polyphenolic extracts. The effect of farming methods on polyphenolic levels was highlighted. The higher reduction of inflammatory mediators release in extracts from plants cultivated under mineral fertilisation treatment was correlated to the higher amount of quercetin. These results can be useful for both nutraceutical or agronomic purposes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  1. Molecular characterization of a divergent strain of calla lily chlorotic spot virus infecting celtuce (Lactuca sativa var. augustana) in China.

    Science.gov (United States)

    Wu, Xiaodong; Wu, Xiaoyun; Li, Wenbin; Cheng, Xiaofei

    2018-02-01

    Through sequencing and assembly of small RNAs, an orthotospovirus was identified from a celtuce plant (Lactuca sativa var. augustana) showing vein clearing and chlorotic spots in the Zhejiang province of China. The S, M, and L RNAs of this orthotospovirus were determined to be 3146, 4734, and 8934 nt, respectively, and shared 30.4-72.5%, 43.4-80.8%, and 29.84-82.9% nucleotide sequence identities with that of known orthotospoviruses. The full length nucleoprotein (N) of this orthotospovirus shared highest amino acid sequence identity (90.25%) with that of calla lily chlorotic spot virus isolated from calla lily (CCSV-calla) [China: Taiwan: 2001] and tobacco (CCSV-LJ1) [China: Lijiang: 2014]. Phylogenetic analyses showed that this orthotospovirus is phylogenetically associated with CCSV isolates and clustered with CCSV, tomato zonate spot virus (TZSV), and tomato necrotic spot-associated virus (TNSaV) in a separate sub-branch. These results suggest that this orthotospovirus is a divergent isolate of CCSV and was thus named CCSV-Cel [China: Zhejiang: 2017].

  2. Validation of a Method for Cylindrospermopsin Determination in Vegetables: Application to Real Samples Such as Lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Prieto, Ana I; Guzmán-Guillén, Remedios; Díez-Quijada, Leticia; Campos, Alexandre; Vasconcelos, Vitor; Jos, Ángeles; Cameán, Ana M

    2018-02-01

    Reports on the occurrence of the cyanobacterial toxin cylindrospermopsin (CYN) have increased worldwide because of CYN toxic effects in humans and animals. If contaminated waters are used for plant irrigation, these could represent a possible CYN exposure route for humans. For the first time, a method employing solid phase extraction and quantification by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) of CYN was optimized in vegetables matrices such as lettuce ( Lactuca sativa ). The validated method showed a linear range, from 5 to 500 ng CYN g -1 of fresh weight (f.w.), and detection and quantitation limits (LOD and LOQ) of 0.22 and 0.42 ng CYN g -1 f.w., respectively. The mean recoveries ranged between 85 and 104%, and the intermediate precision from 12.7 to 14.7%. The method showed to be robust for the three different variables tested. Moreover, it was successfully applied to quantify CYN in edible lettuce leaves exposed to CYN-contaminated water (10 µg L -1 ), showing that the tolerable daily intake (TDI) in the case of CYN could be exceeded in elderly high consumers. The validated method showed good results in terms of sensitivity, precision, accuracy, and robustness for CYN determination in leaf vegetables such as lettuce. More studies are needed in order to prevent the risks associated with the consumption of CYN-contaminated vegetables.

  3. Effect of salicylhydroxamic acid on endosperm strength and embryo growth of Lactuca sativa L. cv Waldmann's Green seeds

    Science.gov (United States)

    Brooks, C. A.; Mitchell, C. A.

    1988-01-01

    Salicylhydroxamic acid (SHAM) stimulated germination of photosensitive lettuce (Lactuca sativa L. cv Waldmann's Green) seeds in darkness. To determine whether SHAM acts on the embryo or the endosperm, we investigated separately effects of SHAM on growth potential of isolated embryos as well as on endosperm strength. Embryo growth potential was quantified by incubating decoated embryos in various concentrations of osmoticum and measuring subsequent radicle elongation. Growth potential of embryos isolated from seeds pretreated with 4 millimolar SHAM was equal to that of untreated controls. Rupture strength of endosperm tissue excised from seeds pretreated with SHAM was 33% less than that of controls in the micropylar region. To determine if the embryo must be in contact with the endosperm of SHAM to weaken the endosperm, some endosperms were incubated with SHAM only after dissection from seeds. Rupture strength of SHAM-treated, isolated endosperms in the micropylar region was 25% less than that of untreated controls. There was no difference in rupture strength in the cotyledonary region of endosperm isolated from seeds treated with SHAM in buffer or buffer alone. SHAM therefore stimulates germination not by enhancing embryo growth potential, but by weakening the micropylar region of the endosperm enclosing the embryo.

  4. The effects of cover crop on weed control in collard (Brassica olerecea var acephala) and lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Mennan, H; Ngouajio, M; Isik, D; Kose, B; Kaya, E

    2006-01-01

    Leafy vegetables are not very competitive and weed interference can cause considerable yield losses in collard (Brassica olerecea var acephala) and lettuce (Lactuca sativa L.). Currently there are no pre or post emergence herbicides registered for weed control in these vegetables in Turkey. For this reason, alternative weed control strategies need to be developed. Cover crop residue could represent an alternative method of weed management in these crops. Field studies were conducted in 2004 at the Black Sea Agricultural Research Institute experimental field in Samsun, Turkey. The cover crop treatments consisted of Sorghum bicolor (L.) Moench, Sorghum vulgare Pers., Vicia villosa L., Amaranthus cruentus L., Pisum sativum L. and the bare ground with no cover crop. All cover crops were seeded by hand and incorporated into the soil on 11 May, 2004. Each plot was 10 m2 (2 x 5 m) and arranged in a randomized complete block design with four replications. All cover crops were incorporated into the soil by discing on 1 September 2004 at flowering stage of the cover crops. Broadleaved weed species were dominant in the experimental area. Most cover crops established well and S. bicolor biomass was the highest. The number of weed species emerging in all treatments was different at 14 DAD (days after desiccation). Similar results were observed at 28 and 56 DAD. Treatments with Vicia villosa residues had fewer weed species and lower total weed densities than other treatments.

  5. Effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus application rates

    Directory of Open Access Journals (Sweden)

    S. Fatih Ergin

    2016-10-01

    Full Text Available In this study, effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus fertilization rates were investigated. Phosphorus were added into growing media as 0, 50, 100 and 200 mg P2O5/kg with and without mycorrhiza applications. Phosphorus applications significantly increased yield criteria of lettuce according to the control treatment statistically. Mycorrhiza application also significantly increased plant diameter, plant dry weight and phosphor uptake by plant. The highest phosphorus uptakes by plants were determined in 200 mg P2O5/kg treatments as 88.8 mg P/pot with mycorrhiza and 83.1 mg P/pot without mycorrhiza application. In the control at 0 doses of phosphorus with mycorrhiza treatment, phosphorus uptake (69.9 mg P/pot, edible weight (84.36 g, dry weight (8.64 g and leaf number (28 of lettuce were higher than that (47.7 mg P/pot, 59.33 g, 6.75 g and 20, respectively in the control without mycorrhiza application. It was determined that mycorrhiza had positive effect on growth criteria and phosphorus nutrition by lettuce plant, and this effect decreased at higher phosphorus application rates.

  6. Benzoxazolin-2(3H)-one (BOA) induced changes in leaf water relations, photosynthesis and carbon isotope discrimination in Lactuca sativa.

    Science.gov (United States)

    Hussain, M Iftikhar; González, L; Chiapusio, G; Reigosa, M J

    2011-08-01

    The effects are reported here of Benzoxazolin-2(3H)-one (BOA), an allelopathic compound, on plant water relations, growth, components of chlorophyll fluorescence, and carbon isotope discrimination in lettuce (Lactuca sativa L.). Lettuce seedlings were grown in 1:1 Hoagland solution in perlite culture medium in environmentally controlled glasshouse. After 30 days, BOA was applied at concentration of 0.1, 0.5, 1.0 and 1.5 mM and distilled water (control). BOA, in the range (0.1-1.5 mM), decreased the shoot length, root length, leaf and root fresh weight. Within this concentration range, BOA significantly reduced relative water content while leaf osmotic potential remained unaltered. Stress response of lettuce was evaluated on the basis of six days of treatment with 1.5 mM BOA by analyzing several chlorophyll fluorescence parameters determined under dark-adapted and steady state conditions. There was no change in initial fluorescence (F₀) in response to BOA treatment while maximum chlorophyll fluorescence (F(m)) was significantly reduced. BOA treatment significantly reduced variable fluorescence (F(v)) on first, second, third, fourth, fifth and sixth day. Quantum efficiency of open PSII reaction centers (F(v)/F(m)) in the dark-adapted state was significantly reduced in response to BOA treatment. Quantum yield of photosystem II (ΦPSII) electron transport was significantly reduced because of decrease in the efficiency of excitation energy trapping of PSII reaction centers. Maximum fluorescence in light-adapted leaves (F'(m)) was significantly decreased but there was no change in initial fluorescence in light-adapted state (F'₀) in response to 1.5 mM BOA treatment. BOA application significantly reduced photochemical fluorescence quenching (qP) indicating that the balance between excitation rate and electron transfer rate has changed leading to a more reduced state of PSII reaction centers. Non photochemical quenching (NPQ) was also significantly reduced by BOA

  7. Ion irradiation-induced, localized sp2 to sp3 hybridized carbon transformation in walls of multiwalled carbon nanotubes

    Science.gov (United States)

    Kumari, Reetu; Singh, Fouran; Yadav, Brajesh S.; Kotnala, Ravinder K.; Peta, Koteswara Rao; Tyagi, Pawan K.; Kumar, Sanjeev; Puri, Nitin K.

    2017-12-01

    In this report, ion irradiation-induced localized sp2 to sp3 hybridized carbon transformation in multiwalled carbon nanotubes (MWCNTs) was observed after irradiating MWCNTs with high-energy Au+8 ions (100 MeV). The used MWCNTs were grown using cobaltocene and benzene as catalyst and carbon source, respectively by the thermal CVD technique and consist of both unfilled and Co-filled tubes. Prior to irradiation, the MWCNT sample was characterized using scanning electron microscope and micro-Raman and photoluminescence spectrometers. The effect of ion fluence on MWCNT walls and transformation of sp2 to sp3 sites was analyzed by Raman spectroscopy, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. We found that as the fluence increased, the localized transformation from sp2 to sp3 sites occurred in the walls of MWCNTs, which was evident by the emergence of peak at approximately 1543 cm-1 associated with the G peak in tetrahedral amorphous carbon (ta-C) and the vanishing of 2D band (2700 cm-1). Furthermore, we observed broadening in D and G, with slight shift in their positions and consistent decrease in 2D band intensity, as fluence increased.

  8. Control of Branchionus sp. and Amoeba sp. in cultures of Arthrospira sp. Control de Branchionus sp. y Amoeba sp. en cultivos de Arthrospira sp.

    Directory of Open Access Journals (Sweden)

    Carlos Méndez

    2012-09-01

    Full Text Available Cultivation of cyanobacterium Arthrospira sp. has been developed in many countries for the production of proteins, pigments and other compounds. Outdoor mass cultures are often affected by biological contamination, drastically reducing productivity as far as bringing death. This study evaluates the control of Branchionus sp. and Amoeba sp. with two chemical compounds: urea (U and ammonium bicarbonate (AB, in laboratory conditions and outdoor mass culture of Arthrospira sp. The lethal concentration 100 (LC100 at 24 h for Branchionus sp. and Amoeba sp. determined was of 60-80 mg L-1 (U and 100-150 mg L-1 (AB. The average effective inhibition concentration for 50% of the population (IC50 in Arthrospira sp., after 72 h, was 80 mg L-1 (U and 150 mg L-1 (AB. The application of doses of 60 mg L-1 (U or 100 mg L-1 (AB in the outdoor mass culture of this contaminated microalga, completely inhibited grazing and did not affect the growth of Arthrospira sp. but rather promoted rapid recovery of algal density at levels prior to infestation. These compounds provided an economical and effective control of predators in cultures of Arthrospira sp.El cultivo de la cianobacteria Arthrospira sp. ha sido desarrollado en muchos países para la obtención de proteínas, pigmentos y otros compuestos. Cultivo que a nivel industrial se ve afectado frecuentemente por contaminación biológica, reduciendo drásticamente la productividad hasta causar la muerte. Este estudio evalúa el control de Branchionus sp. y de Amoeba sp. con dos compuestos químicos, la urea (U y bicarbonato de amonio (AB en cultivos de Arthrospira sp. La concentración letal 100 (LC100 determinada a las 24 h para Branchionus sp. y Amoeba sp. fue de 60-80 mg L-1 (U y 100-150 mg L-1 (AB. La concentración media de inhibición efectiva, después de 72 h, para el 50% de la población (IC50 en Arthrospira fue de 80 mg L-1 (U y 150 mg L-1 (AB. La aplicación de dosis de 60 mg L-1 (U ó 100 mg L-1 (AB en

  9. Growth kinetics and biodeterioration of polypropylene microplastics by Bacillus sp. and Rhodococcus sp. isolated from mangrove sediment.

    Science.gov (United States)

    Auta, H S; Emenike, C U; Jayanthi, B; Fauziah, S H

    2018-02-01

    Interest in the biodegradation of microplastics is due to their ubiquitous distribution, availability, high persistence in the environment and deleterious impact on marine biota. The present study evaluates the growth response and mechanism of polypropylene (PP) degradation by Bacillus sp. strain 27 and Rhodococcus sp. strain 36 isolated from mangrove sediments upon exposure to PP microplastics. Both bacteria strains were able to utilise PP microplastic for growth as confirmed by the reduction of the polymer mass. The weight loss was 6.4% by Rhodococcus sp. strain 36 and 4.0% by Bacillus sp. strain 27 after 40days of incubation. PP biodegradation was further confirmed using Fourier-transform infrared spectroscopy and scanning electron microscopy analyses, which revealed structural and morphological changes in the PP microplastics with microbial treatment. These analyses showed that the isolates can colonise, modify and utilise PP microplastics as carbon source. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. EFEITO DE DIFERENTES RESÍDUOS ORGÂNICOS NO DESENVOLVIMENTO E NA PRODUTIVIDADE DA ALFACE (Lactuca sativa L. EFFECT OF DIFFERENT ORGANIC RESIDUES IN THE DEVELOPMENT AND IN THE PRODUCTIVITY OF LETTUCE (Lactuca sativa L

    Directory of Open Access Journals (Sweden)

    José Xavier de Almeida Neto

    2007-09-01

    Full Text Available

    O presente trabalho teve o objetivo de verificar o efeito das adubações orgânica e química e a mistura das mesmas, e também avaliar o comportamento dos estercos de galinhas e de bovinos no desenvolvimento e na produtividade da alface (Lactuca sativa L.. O experimento foi conduzido na Escola de Agronomia da Universidade Federal de Goiás, em LE., usando a cultivar Regina (Vigoragro. O delineamento foi inteiramente casualizado, constando de sete tratamentos: 1 testemunha (sem adubação; 2 adubação química + esterco bovino; 3 adubação química, sem adubação orgânica; 4 esterco de galinhas (dobro da dose recomendada, sem adubação química; 5 esterco bovino (dobro da dose, sem adubação química; 6 adubação química + esterco de galinhas; 7 adubação química (dobro da dose, tendo-se empregado as quantidades segundo as recomendações da C.F.S., para Goiás (1988. Os resultados obtidos mostraram que os tratamentos 2, 5 e 6 foram significativamente iguais entre si e superiores aos demais, em todas as variáveis analisadas (peso, diâmetro e valor comercial.

    The present study was done to verify the effect of organic and chemical fertilizations either together or separated, on the productivity of lettuce (Lactuca sativa L. The influence of chicken and cattle manure on the lettuce productivity was also verified. The field experiment was conducted at the Escola de Agronomia, U.F.G., Goiânia, Goiás (Brazil, in dark red latosol (oxisol, using the cultivar ‘Reqina’ (seeds from Vigoragro. The experimental design was completely randomized, with seven treatments, as follow: 1 testimony (without fertilization; 2 chemical fertilization + cattle manure; 3 chemical fertilization, without manure fertilization; 4 chicken manure (double of the recommended level, without chemical fertilization; 5

  11. Lettuce (Lactuca sativa L. seedling production with different sources of phosphate and phosphate solubilizing microorganisms / Produção de mudas de alface (Lactuca sativa L. em presença de diferentes fontes fosfatadas e microrganismos

    Directory of Open Access Journals (Sweden)

    Germano Nunes Silva Filho

    2009-10-01

    Full Text Available The objective of this work was to evaluate the behaviour of phosphate solubilizing microorganisms (fungus: 310A, 061, 062 e 251, bacterias 163, 160 e 161 in promoting nutrition and growth of lettuce(Lactuca sativa L. seedlings cultivated in trays with sterilized substrate fertilized and phosphates source. A randomized completely design was used, with a factorial 4x8 scheme (four treatments with phosphate nutrition and inoculated with eight phosphate solubilizing microorganisms and four replications. Each replication was made of 10 cells. The experiment was evaluated 35 days after planting for dry matter, P percentage and total phosphorus of above ground parts. The triple super phosphate (SFT had better results than the others, including the control treatment, in all analyzed parameters. On the dry matter production, it was observed negative effect from inoculation in five treatments fertilized with SFT. There was no effect of isolates on the phosphorus content values. In the values of total phosphorus, the isolates 061, 062 e 163 increased the parameter values on the fertilized treatment with SFT. The natural phosphates presented low efficiency when compared to dissolvable fertilizer on the availability of phosphorus to the plants.O objetivo deste trabalho foi avaliar o comportamento de microrganismos solubilizadores de fosfatos (fungos: 310A, 061, 062 e 251; bactérias: 163, 160 e 161 na promoção da nutrição e crescimento de mudas de alface (Lactuca sativa L., cultivadas em bandejas com substrato esterilizado e adubadas com fontes fosfatadas. Foi utilizado um delineamento inteiramente casualizado, arranjo fatorial 4 x 8 (quatro tratamentos de adubação fosfatada e oito tratamentos de inoculação microrganismos solubilizadores de fosfatos com quatro repetições por isolado. Cada repetição foi constituída de 10 células. Aos 35 dias de cultivo, as plantas foram colhidas avaliando-se a matéria seca, porcentagem de P e P total da parte a

  12. Tsukamurella pulmonis sp. nov.

    Science.gov (United States)

    Yassin, A F; Rainey, F A; Brzezinka, H; Burghardt, J; Rifai, M; Seifert, P; Feldmann, K; Schaal, K P

    1996-04-01

    Chemotaxonomic and 16S ribosomal DNA sequence analyses of an isolate from the sputum of a patient with a mycobacterial lung infection clearly delineated a new species of the genus Tsukamurella. This new species can be defined on the basis of genotypic and phenotypic data. The name Tsukamurella pulmonis sp. nov. is proposed for this organism; the type strain is IMMIB D-1321T (= DSM 44142T). This isolate shows 44.2 and 36.2% DNA relatedness to Tsukamurella paurometabola DSM 20162T (T = type strain) and Tsukamurella inchonensis DSM 44067T, respectively.

  13. Methanosarcina Play an Important Role in Anaerobic Co-Digestion of the Seaweed Ulva lactuca: Taxonomy and Predicted Metabolism of Functional Microbial Communities.

    Directory of Open Access Journals (Sweden)

    Jamie A FitzGerald

    Full Text Available Macro-algae represent an ideal resource of third generation biofuels, but their use necessitates a refinement of commonly used anaerobic digestion processes. In a previous study, contrasting mixes of dairy slurry and the macro-alga Ulva lactuca were anaerobically digested in mesophilic continuously stirred tank reactors for 40 weeks. Higher proportions of U. lactuca in the feedstock led to inhibited digestion and rapid accumulation of volatile fatty acids, requiring a reduced organic loading rate. In this study, 16S pyrosequencing was employed to characterise the microbial communities of both the weakest (R1 and strongest (R6 performing reactors from the previous work as they developed over a 39 and 27-week period respectively. Comparing the reactor communities revealed clear differences in taxonomy, predicted metabolic orientation and mechanisms of inhibition, while constrained canonical analysis (CCA showed ammonia and biogas yield to be the strongest factors differentiating the two reactor communities. Significant biomarker taxa and predicted metabolic activities were identified for viable and failing anaerobic digestion of U. lactuca. Acetoclastic methanogens were inhibited early in R1 operation, followed by a gradual decline of hydrogenotrophic methanogens. Near-total loss of methanogens led to an accumulation of acetic acid that reduced performance of R1, while a slow decline in biogas yield in R6 could be attributed to inhibition of acetogenic rather than methanogenic activity. The improved performance of R6 is likely to have been as a result of the large Methanosarcina population, which enabled rapid removal of acetic acid, providing favourable conditions for substrate degradation.

  14. Methanosarcina Play an Important Role in Anaerobic Co-Digestion of the Seaweed Ulva lactuca: Taxonomy and Predicted Metabolism of Functional Microbial Communities.

    Science.gov (United States)

    FitzGerald, Jamie A; Allen, Eoin; Wall, David M; Jackson, Stephen A; Murphy, Jerry D; Dobson, Alan D W

    2015-01-01

    Macro-algae represent an ideal resource of third generation biofuels, but their use necessitates a refinement of commonly used anaerobic digestion processes. In a previous study, contrasting mixes of dairy slurry and the macro-alga Ulva lactuca were anaerobically digested in mesophilic continuously stirred tank reactors for 40 weeks. Higher proportions of U. lactuca in the feedstock led to inhibited digestion and rapid accumulation of volatile fatty acids, requiring a reduced organic loading rate. In this study, 16S pyrosequencing was employed to characterise the microbial communities of both the weakest (R1) and strongest (R6) performing reactors from the previous work as they developed over a 39 and 27-week period respectively. Comparing the reactor communities revealed clear differences in taxonomy, predicted metabolic orientation and mechanisms of inhibition, while constrained canonical analysis (CCA) showed ammonia and biogas yield to be the strongest factors differentiating the two reactor communities. Significant biomarker taxa and predicted metabolic activities were identified for viable and failing anaerobic digestion of U. lactuca. Acetoclastic methanogens were inhibited early in R1 operation, followed by a gradual decline of hydrogenotrophic methanogens. Near-total loss of methanogens led to an accumulation of acetic acid that reduced performance of R1, while a slow decline in biogas yield in R6 could be attributed to inhibition of acetogenic rather than methanogenic activity. The improved performance of R6 is likely to have been as a result of the large Methanosarcina population, which enabled rapid removal of acetic acid, providing favourable conditions for substrate degradation.

  15. Análisis técnico de producción de tilapia Oreochromis niloticus y lechuga acrópolis Lactuca sativa en acuaponia

    OpenAIRE

    Rubio Cabrera, Sheila Guadalupe

    2014-01-01

    Se evaluó la producción de tilapia Oreochromis niloticus y lechuga romana acropolis Lactuca sativa en sistemas acuapónicos utilizando dos sistemas: recirculación de agua sin recambio (utilizando biofiltración) y sistema sin recirculación con recambio parcial de agua. El cultivo se realizó en 4 etapas. En la primera se colocaron 800 alevines de O. niloticus de 0.2 g de peso inicial en tinas plásticas de 800 L (1600 organismos/m3de agua) durante 39 días. La segunda etapa con u...

  16. [Seasonal variations of metal contents (Cd, Cu, Fe, Mn and Zn) in seaweed Ulva lactuca from the coast of El Jadida city (Morocco)].

    Science.gov (United States)

    Kaimoussi, Aziz; Mouzdahir, Abdelkrim; Saih, Abdelkbir

    2004-04-01

    The quality of El Jadida Atlantic coastal water was monitored from April 1998 to March 1999 by measuring hydrological parameters (dissolved oxygen, suspended particulate matter, phosphates and nitrites) and using the seaweed Ulva lactuca as a quantitative bio-indicator of cadmium, copper, iron, manganese and zinc contamination. Metal content in seaweeds, collected every month from four stations characterized by the discharge of urban and industrial waste water, showed significant variations depending on the station and sampling period. However, the seaweed of El Jadida exhibited generally lower contents compared to those of similar species from other geographical areas.

  17. Influence of diesel contamination in soil on growth and dry matter partitioning of Lactuca sativa and Ipomoea batatas.

    Science.gov (United States)

    Fatokun, Kayode; Zharare, Godfrey Elijah

    2015-09-01

    Phytotoxic effect of diesel contaminated soil was investigated on growth and dry matter partitioning in Lactuca sativa and Ipomoea batatas in greenhouse pot experiment at two concentration range (0-30 ml and 0-6 ml diesel kg(-1) soil) for 14 weeks. The results indicated thatwhole plant biomass, stem length, root length, number of leaves and leaf chlorophyll in two plants were negatively correlated with increasing diesel concentrations. The critical concentration of diesel associated with 10% decrease in plant growth was 0.33 ml for lettuce and 1.50 ml for sweet potato. Thus, growth of lettuce in diesel contaminated soil was more sensitive than sweet potato. The pattern of dry matter partitioning between root and shoot in both plants were similar. In 0-6 ml diesel contamination range, allocation of dry matter to shoot system was favoured resulting in high shoot: root ratio of 4.54 and 12.91 for lettuce and sweet potato respectively. However, in 0-30 ml diesel contamination range, allocation of dry matter to root was favoured, which may have been an adaptive mechanism in which the root system was used for storage in addition to increasing the capacity for foraging for mineral nutrients and water. Although lettuce accumulated more metals in its tissue than sweet potato, the tissue mineral nutrients in both species did not vary to great extent. The critical diesel concentration for toxicity suggested that the cause of mortality and poor growth of sweet potato and lettuce grown in diesel contaminated soil was due to presence of hydrocarbons in diesel.

  18. Impact of non-functionalized and amino-functionalized multiwall carbon nanotubes on pesticide uptake by lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Hamdi, Helmi; De La Torre-Roche, Roberto; Hawthorne, Joseph; White, Jason C

    2015-03-01

    The effect of non-functionalized and amino-functionalized multiwall carbon nanotube (CNT) exposure, as well as the impact of CNT presence on coexistent pesticide accumulation, was investigated in lettuce (Lactuca sativa L.). Lettuce seeds were sown directly into CNT-amended vermiculite (1000 mg L(-1)) to monitor phytotoxicity during germination and growth. During growth, lettuce seedlings were subsequently exposed to chlordane (cis-chlordane [CS], trans-chlordane [TC] and trans-nonachlor [TN]) and p,p'-DDE (all at 100 ng/L) in the irrigation solution for a 19-d growth period. CNT exposure did not significantly influence seed germination (82-96%) or plant growth. Similarly, pesticide exposure had no impact on plant growth, total pigment production or tissue lipid peroxidation. After 19 d, the root content of total chlordane and p,p'-DDE was 390 and 73.8 µg g(-1), respectively; in plants not exposed to CNTs, the shoot levels were 1.58 and 0.40 µg g(-1), respectively. The presence and type of CNT significantly influenced pesticide availability to lettuce seedlings. Non-functionalized CNT decreased the root and shoot pesticide content by 88% and 78%, respectively, but amino-functionalized CNT effects were significantly more modest, with decreases of 57% in the roots and 23% in the shoots, respectively. The presence of humic acid completely reversed the reduced accumulation of pesticides induced by amino-functionalized CNT, likely due to strong competition over adsorption sites on the nanomaterial (NM). These findings have implications for food safety and for the use of engineered NMs in agriculture, especially with leafy vegetables.

  19. Testing the toxicity of metals, phenol, effluents, and receiving waters by root elongation in Lactuca sativa L.

    Science.gov (United States)

    Lyu, Jie; Park, Jihae; Kumar Pandey, Lalit; Choi, Soyeon; Lee, Hojun; De Saeger, Jonas; Depuydt, Stephen; Han, Taejun

    2018-03-01

    Phytotoxicity tests using higher plants are among the most simple, sensitive, and cost-effective of the methods available for ecotoxicity testing. In the present study, a hydroponic-based phytotoxicity test using seeds of Lactuca sativa was used to evaluate the water quality of receiving waters and effluents near two industrial sites (Soyo and Daejon) in Korea with respect to the toxicity of 10 metals (As, Cd, Cr, Cu, Fe, Pb, Mn, Hg, Ni, Zn) and phenol, and of the receiving waters and effluents themselves. First, the L. sativa hydroponic bioassay was used to determine whether the receiving water or effluents were toxic; then, the responsible toxicant was identified. The results obtained with the L. sativa bioassay ranked the EC 50 toxicities of the investigated metal ions and phenol as: Cd > Ni > Cu > Zn > Hg > phenol > As > Mn > Cr > Pb > Fe. We found that Zn was the toxicant principally responsible for toxicity in Daejeon effluents. The Daejeon field effluent had a higher Zn concentration than permitted by the effluent discharge criteria of the Ministry of Environment of Korea. Our conclusion on the importance of Zn toxicity was supported by the results of the L. sativa hydroponic assay, which showed that the concentration of Zn required to inhibit root elongation in L. sativa by 50% (EC 50 ) was higher in the Daejeon field effluent than that of pure Zn. More importantly, we proved that the L. sativa hydroponic test method can be applied not only as an alternative tool for determining whether a given waste is acceptable for discharge into public water bodies, but also as an alternative method for measuring the safety of aquatic environments using EC 20 values, with respect to the water pollutants investigated (i.e., Cd, Cr, Cu, Pb, Mn, Hg, Ni, Zn, and phenol). Copyright © 2017. Published by Elsevier Inc.

  20. Determination of Fatty Acids Profile and Physicochemical Study of Sea Lettuce (Ulva lactuca Oil from Bushehr City Coasts

    Directory of Open Access Journals (Sweden)

    Soror Shaghuli

    2017-05-01

    Full Text Available Background: Sea lettuce is a kind green alga with scientific name "Ulva lactuca", has many uses in many countries. With Notice to the presence of this alga in the coasts of Bushehr and its ease of propagation and cultivation, we can take advantage of beneficial interest. The objectives of this current study was to determine the amount of total fat, survey the quality and quantity of some physicochemical parameters and the profile of fatty acids in its oil. Materials and Methods: After samples collecting of sea lettuce (Sea lettuce from Bushehr coasts, sample preparation and extraction of fat, quantity of some physicochemical parameters according to AOAC method; and fatty acid profile were analyzed by gas chromatography with flame ionization detection (GC-FID. Results: The acidity index in extracted oil in Shoraye-shahr, Bandargah and Naftkesh regions were, 0.73, 0.73 and 0.72 respectively, and the peroxide value was 0.75, 0.74 and 0.75 respectively. The refractive index and average oil contents for all areas were reported 3 % and 1412, respectively. In the three mentioned regions, sixteen fatty acids including (C6, (C10, (C12, (C13, (C14, (C15, (C16, (C17, (C18, (C19, (C20, (C21, (C18: 1, (C18: 2, (C18: 3 were identified with different amounts. Palmitic acid had the highest levels in all three regions. Conclusion: Sea lettuce contains different fatty acids that each of them has different applications in food industry, medicine and cosmetics. The favorable amounts of omega-3 and omega-6 fatty acids in the sea lettuce oil increase their nutritional importance. Caltivating of this beneficial alga is suggested due to the appropriate geographic climate of Bushehr.

  1. Root exudation and root development of lettuce (Lactuca sativa L.cv. Tizian as affected by different soils

    Directory of Open Access Journals (Sweden)

    Günter eNeumann

    2014-01-01

    Full Text Available Development and activity of plant roots exhibits high adaptive variability. Although it is well-documented, that physicochemical soil properties can strongly influence root morphology and root exudation, particularly under field conditions, a comparative assessment is complicated by the impact of additional factors, such as climate and cropping history. To overcome these limitations, in this study, field soils originating from an unique experimental plot system with three different soil types, which were stored at the same field site for ten years and exposed to the same agricultural management practice, were used for an investigation on effects of soil type on root development and root exudation. Lettuce (Lactuca sativa L. cv. Tizian was used as a model plant, grown under controlled environmental conditions in a minirhizotrone system equipped with root observation windows (rhizoboxes. Root exudates were collected by placing sorption filters onto the root surface followed by subsequent extraction and GC-MS profiling of the trapped compounds. Surprisingly, even in absence of external stress factors with known impact on root exudation, such as pH extremes, water and nutrient limitations/toxicities or soil structure effects (use of sieved soils, root growth characteristics (root length, fine root development as well as profiles of root exudates were strongly influenced by the soil type used for plant cultivation. The results coincided well with differences in rhizosphere bacterial communities, detected in field-grown lettuce plants cultivated on the same soils (Schreiter et al., this issue. The findings suggest that the observed differences may be the result of plant interactions with the soil-specific microbiomes.

  2. Silencing the lettuce homologs of small rubber particle protein does not influence natural rubber biosynthesis in lettuce (Lactuca sativa).

    Science.gov (United States)

    Chakrabarty, Romit; Qu, Yang; Ro, Dae-Kyun

    2015-05-01

    Natural rubber, cis-1,4-polyisoprene, is an important raw material in chemical industries, but its biosynthetic mechanism remains elusive. Natural rubber is known to be synthesized in rubber particles suspended in laticifer cells in the Brazilian rubber tree (Hevea brasiliensis). In the rubber tree, rubber elongation factor (REF) and its homolog, small rubber particle protein (SRPP), were found to be the most abundant proteins in rubber particles, and they have been implicated in natural rubber biosynthesis. As lettuce (Lactuca sativa) can synthesize natural rubber, we utilized this annual, transformable plant to examine in planta roles of the lettuce REF/SRPP homologs by RNA interference. Among eight lettuce REF/SRPP homologs identified, transcripts of two genes (LsSRPP4 and LsSRPP8) accounted for more than 90% of total transcripts of REF/SRPP homologs in lettuce latex. LsSRPP4 displays a typical primary protein sequence as other REF/SRPP, while LsSRPP8 is twice as long as LsSRPP4. These two major LsSRPP transcripts were individually and simultaneously silenced by RNA interference, and relative abundance, polymer molecular weight, and polydispersity of natural rubber were analyzed from the LsSRPP4- and LsSRPP8-silenced transgenic lettuce. Despite previous data suggesting the implications of REF/SRPP in natural rubber biosynthesis, qualitative and quantitative alterations of natural rubber could not be observed in transgenic lettuce lines. It is concluded that lettuce REF/SRPP homologs are not critically important proteins in natural rubber biosynthesis in lettuce. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Bioavailability of silver and silver sulfide nanoparticles to lettuce (Lactuca sativa): Effect of agricultural amendments on plant uptake.

    Science.gov (United States)

    Doolette, Casey L; McLaughlin, Michael J; Kirby, Jason K; Navarro, Divina A

    2015-12-30

    Silver nanoparticles (AgNPs) can enter terrestrial systems as sulfidised AgNPs (Ag2S-NPs) through the application of biosolids to soil. However, the bioavailability of Ag2S-NPs in soils is unknown. The two aims of this study were to investigate (1) the bioavailability of Ag to lettuce (Lactuca sativa) using a soil amended with biosolids containing Ag2S-NPs and (2) the effect of commonly used agricultural fertilisers/amendments on the bioavailability of Ag, AgNPs and Ag2S-NPs to lettuce. The study used realistic AgNP exposure pathways and exposure concentrations. The plant uptake of Ag from biosolids-amended soil containing Ag2S-NPs was very low for all Ag treatments (0.02%). Ammonium thiosulfate and potassium chloride fertilisation significantly increased the Ag concentrations of plant roots and shoots. The extent of the effect varied depending on the type of Ag. Ag2S-NPs, the realistic form of AgNPs in soil, had the lowest bioavailability. The potential risk of AgNPs in soils is low; even in the plants that had the highest Ag concentrations (Ag(+)+thiosulfate), only 0.06% of added Ag was found in edible plant parts (shoots). Results from the study suggest that agricultural practises must be considered when carrying out risk assessments of AgNPs in terrestrial systems; such practises can affect AgNP bioavailability. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Experimental determinations of soil copper toxicity to lettuce (Lactuca sativa) growth in highly different copper spiked and aged soils.

    Science.gov (United States)

    Christiansen, Karen S; Borggaard, Ole K; Holm, Peter E; Vijver, Martina G; Hauschild, Michael Z; Peijnenburg, Willie J G M

    2015-04-01

    Accurate knowledge about factors and conditions determining copper (Cu) toxicity in soil is needed for predicting plant growth in various Cu-contaminated soils. Therefore, effects of Cu on growth (biomass production) of lettuce (Lactuca sativa) were tested on seven selected, very different soils spiked with Cu and aged for 2 months at 35 °C. Cu toxicity was expressed as pEC50(Cu(2+)), i.e., the negative logarithm of the EC50(Cu(2+)) activity to plant growth. The determined pEC50(Cu(2+)) was significantly and positively correlated with both the analytically readily available soil pH and concentration of dissolved organic carbon [DOC] which together could explain 87% of the pEC50(Cu(2+)) variation according to the simple equation: pEC50(Cu(2+)) = 0.98 × pH + 345 × [DOC] - 0.27. Other soil characteristics, including the base cation concentrations (Na(+), K(+), Ca(2+), Mg(2+)), the cation exchange capacity at soil pH (ECEC), and at pH 7 (CEC7), soil organic carbon, clay content, and electric conductivity as well as the distribution coefficient (Kd) calculated as the ratio between total soil Cu and water-extractable Cu did not correlate significantly with pEC50(Cu(2+)). Consequently, Cu toxicity, expressed as the negative log of the Cu(2+) activity, to plant growth increases at increasing pH and DOC, which needs to be considered in future management of plant growth on Cu-contaminated soils. The developed regression equation allows identification of soil types in which the phytotoxicity potential of Cu is highest.

  5. Root exudation and root development of lettuce (Lactuca sativa L. cv. Tizian) as affected by different soils

    Science.gov (United States)

    Neumann, G.; Bott, S.; Ohler, M. A.; Mock, H.-P.; Lippmann, R.; Grosch, R.; Smalla, K.

    2014-01-01

    Development and activity of plant roots exhibit high adaptive variability. Although it is well-documented, that physicochemical soil properties can strongly influence root morphology and root exudation, particularly under field conditions, a comparative assessment is complicated by the impact of additional factors, such as climate and cropping history. To overcome these limitations, in this study, field soils originating from an unique experimental plot system with three different soil types, which were stored at the same field site for 10 years and exposed to the same agricultural management practice, were used for an investigation on effects of soil type on root development and root exudation. Lettuce (Lactuca sativa L. cv. Tizian) was grown as a model plant under controlled environmental conditions in a minirhizotrone system equipped with root observation windows (rhizoboxes). Root exudates were collected by placing sorption filters onto the root surface followed by subsequent extraction and GC-MS profiling of the trapped compounds. Surprisingly, even in absence of external stress factors with known impact on root exudation, such as pH extremes, water and nutrient limitations/toxicities or soil structure effects (use of sieved soils), root growth characteristics (root length, fine root development) as well as profiles of root exudates were strongly influenced by the soil type used for plant cultivation. The results coincided well with differences in rhizosphere bacterial communities, detected in field-grown lettuce plants cultivated on the same soils (Schreiter et al., this issue). The findings suggest that the observed differences may be the result of plant interactions with the soil-specific microbiomes. PMID:24478764

  6. Report of the first human case of Caulobacter sp. infection

    DEFF Research Database (Denmark)

    Justesen, Ulrik S; Holt, Hanne M; Thiesson, Helle

    2007-01-01

    A Caulobacter sp. isolate was recovered from the dialysis fluid of a patient undergoing peritoneal dialysis. Bacterial identification included electron microscopy and 16S rDNA sequencing. To our knowledge, this is the first report of human Caulobacter infection. Special growth requirements sugges...

  7. Corrosion of mild steel and stainless steel by marine Vibrio sp.

    Digital Repository Service at National Institute of Oceanography (India)

    PrabhaDevi; Wagh, A.B.

    Microbially induced corrosion (MIC) of stainless steel and mild steel coupons exposed to media with and without a bacterial culture Vibrio sp. was studied using Scanning Electron Microscope (SEM). Pitting type of corrosion was noticed which was more...

  8. Estudo da ocorrência de enteroparasitas em hortaliças comercializadas na região metropolitana de São Paulo - SP, Brasil: II - Pesquisa de protozoários intestinais Study of the occurrence of intestinal parasites os vegetables comercially traded in the metropolitan area of S.Paulo, SP - Brazil: II - Research into protozoan cysts

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Fernandes de Oliveira

    1992-10-01

    Full Text Available Foram analisadas hortaliças "in natura", comercializadas na Região Metropolitana de São Paulo, SP-Brasil, visando à pesquisa e à identificação de cistos de protozoários de interesse médico. As hortaliças, constituídas de 50 amostras de cada variedade, consistiram em: alface (Lactuca sativa, variedades lisa e crespa, escarola (Chichorium sp e agrião (Nasturtium officinale. Os resultados evidenciaram elevados percentuais de contaminação em todas as variedades de hortaliças analisadas, porém as freqüências de protozoários foram maiores no agrião. As amostras de alfaces apresentaram os menores percentuais de contaminação, enquanto que a escarola apresentou valores geralmente situados entre o agrião e as alfaces. Observou-se uma grande variedade de protozoários, cujas freqüências de ocorrência na população residente na Região Metropolitana de São Paulo são igualmente elevadas. Os mais freqüentes foram Entamoeba sp (com 4 e 8 núcleos e Giardia sp. Foram também isolados cistos de Iodamoeba sp, Endolimax sp e Chilomastix sp. Os elevados níveis de contaminação fecal encontrados nas amostras analisadas apontam para a importância dos alimentos na transmissão de protozoários intestinais.Vegetables in natura , commercially traded in the metropolitan area of S.Paulo, Brazil, were analised by means of the appropriate methodology with a view to discovering and identifying protozoan cysts of medical interest. The vegetables under study consisted of 50 samples of each of the variaties listed bel ow: lettuce (Lactuca sativa - oily leaves and crisphead varieties, endive (Chicorium sp and water-cress (Nasturtium officinale. Results showed high rates of contamination in all the varieties of vegetable analysed. However, the water-cress was the one which presented the highest frequencies of enteroparasites. Both the oily leafes and crisphead varieties of lettuce presented the lowest rates of contamination, whereas endive

  9. Comparative study on the degradation of dibutyl phthalate by two newly isolated Pseudomonas sp. V21b and Comamonas sp. 51F

    Directory of Open Access Journals (Sweden)

    Vinay Kumar

    2017-09-01

    Full Text Available Dibutyl phthalate is (DBP the top priority toxicant responsible for carcinogenicity, teratogenicity and endocrine disruption. This study demonstrates the DBP degradation capability of the two newly isolated bacteria from municipal solid waste leachate samples. The isolated bacteria were designated as Pseudomonas sp. V21b and Comamonas sp. 51F after scanning electron microscopy, transmission electron microscopy, Gram-staining, antibiotic sensitivity tests, biochemical characterization, 16S-rRNA gene identification and phylogenetic studies. They were able to grow on DBP, benzyl butyl phthalate, monobutyl phthalate, diisodecyl phthalate, dioctyl phthalate, and protocatechuate. It was observed that Pseudomonas sp. V21b was more efficient in DBP degradation when compared with Comamonas sp. 51F. It degraded 57% and 76% of the initial DBP in minimal salt medium and in DBP contaminated samples respectively. Kinetics for the effects of DBP concentration on Pseudomonas sp. V21b and Comamonas sp. 51F growth was also evaluated. Stoichiometry for DBP degradation and biomass formation were compared for both the isolates. Two major metabolites diethyl phthalate and monobutyl phthalates were identified using GC–MS in the extracts. Key genes were amplified from the genomes of Pseudomonas sp. V21b and Comamonas sp. 51F. DBP degradation pathway was also proposed.

  10. Acetobacter intermedius, sp. nov.

    Science.gov (United States)

    Boesch, C; Trcek, J; Sievers, M; Teuber, M

    1998-03-01

    Strains of a new species in the genus Acetobacter, for which we propose the name A. intermedius sp. nov., were isolated and characterized in pure culture from different sources (Kombucha beverage, cider vinegar, spirit vinegar) and different countries (Switzerland, Slovenia). The isolated strains grow in media with 3% acetic acid and 3% ethanol as does A. europaeus, do, however, not require acetic acid for growth. These characteristics phenotypically position A. intermedius between A. europaeus and A. xylinus, DNA-DNA hybridizations of A. intermedius-DNA with DNA of the type strains of Acetobacter europaeus, A. xylinus, A. aceti, A. hansenii, A. liquefaciens, A. methanolicus, A. pasteurianus, A. diazotrophicus, Gluconobacter oxydans and Escherichia coli HB 101 indicated less than 60% DNA similarity. The important features of the new species are described. Acetobacter intermedius strain TF2 (DSM11804) isolated from the liquid phase of a tea fungus beverage (Kombucha) is the type strain.

  11. Tsukamurella tyrosinosolvens sp. nov.

    Science.gov (United States)

    Yassin, A F; Rainey, F A; Burghardt, J; Brzezinka, H; Schmitt, S; Seifert, P; Zimmermann, O; Mauch, H; Gierth, D; Lux, I; Schaal, K P

    1997-07-01

    Chemotaxonomic and 16S ribosomal DNA sequence analyses of four bacterial isolates from blood cultures from patients with cardiac pacemaker implants and sputa of patients with chronic lung infections clearly demonstrated that these bacteria belong to the genus Tsukamurella. DNA-DNA hybridization data, as well as the physiological characteristics of the isolates, indicate that they are closely related and belong to a single species that differs from previously described members of the genus Tsukamurella. The name Tsukamurella tyrosinosolvens sp. nov. is proposed for these isolates, and the new species is represented by strain IMMIB D-1397T (= DSM 44234T). Strain IMMIB D-1397T exhibits 53.4, 53.5, and 54.7% DNA-DNA relatedness to Tsukamurella paurometabola DSM 20162T, Tsukamurella inchonensis DSM 44067T, and Tsukamurella pulmonis DSM 44142T, respectively.

  12. Toxic effect of high concentration of sonochemically synthesized polyvinylpyrrolidone-coated silver nanoparticles on Citrobacter sp. A1 and Enterococcus sp. C1.

    Science.gov (United States)

    Lau, Chew Ping; Abdul-Wahab, Mohd Firdaus; Jaafar, Jafariah; Chan, Giek Far; Abdul Rashid, Noor Aini

    2017-08-01

    Currently, silver nanoparticles (AgNPs) have gained importance in various industrial applications. However, their impact upon release into the environment on microorganisms remains unclear. The aim of this study was to analyze the effect of polyvinylpyrrolidone-capped AgNPs synthesized in this laboratory on two bacterial strains isolated from the environment, Gram-negative Citrobacter sp. A1 and Gram-positive Enterococcus sp. C1. Polyvinylpyrrolidone-capped AgNPs were synthesized by ultrasound-assisted chemical reduction. Characterization of the AgNPs involved UV-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy. Citrobacter sp. A1 and Enterococcus sp. C1 were exposed to varying concentrations of AgNPs, and cell viability was determined. Scanning electron microscopy was performed to evaluate the morphological alteration of both species upon exposure to AgNPs at 1000 mg/L. The synthesized AgNPs were spherical in shape, with an average particle size of 15 nm. The AgNPs had different but prominent effects on either Citrobacter sp. A1 or Enterococcus sp. C1. At an AgNP concentration of 1000 mg/L, Citrobacter sp. A1 retained viability for 6 hours, while Enterococcus sp. C1 retained viability only for 3 hours. Citrobacter sp. A1 appeared to be more resistant to AgNPs than Enterococcus sp. C1. The cell wall of both strains was found to be morphologically altered at that concentration. Minute and spherical AgNPs significantly affected the viability of the two bacterial strains selected from the environment. Enterococcus sp. C1 was more vulnerable to AgNPs, probably due to its cell wall architecture and the absence of silver resistance-related genes. Copyright © 2015. Published by Elsevier B.V.

  13. Space-time monitoring of coastal pollution in the Gulf of Gaeta, Italy, using δ15N values of Ulva lactuca, landscape hydromorphology, and Bayesian Kriging modelling.

    Science.gov (United States)

    Rossi, Loreto; Calizza, Edoardo; Careddu, Giulio; Rossi, David; Orlandi, Lucia; Jona-Lasinio, Giovanna; Aguzzi, Laura; Costantini, Maria Letizia

    2018-01-01

    We investigated the space-time dynamics of N pollution in a Mediterranean gulf (Gulf of Gaeta) by means of δ 15 N variation in seaweed fronds (Ulva lactuca) previously collected from an unpolluted habitat. We used a comprehensive deployment grid that enabled the generation of isotopic seascapes (isoseascapes) describing the topography of N pollution in coastal waters and identifying N input hotspots and their pathways of dispersion at sea. The δ 15 N values of U. lactuca increased during 48h of exposure to the gulf waters, indicating anthropogenic N inputs from wastewater-derived sources. Comparison of the isoseascapes between two years differing in terms of rainfall identified coastal and offshore areas that were vulnerable to freshwater-transported nutrients, consistent with terrestrial hydromorphology and sea surface-water circulation. Isoseacapes were robust enough to reduce deployment effort, representing a powerful tool for monitoring and management strategies and useful for Environmental Protection Agencies, the main target audience of applied ecological research. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Performance and feeding behaviour of two biotypes of the black currant-lettuce aphid, Nasonovia ribisnigri, on resistant and susceptible Lactuca sativa near-isogenic lines.

    Science.gov (United States)

    ten Broeke, Cindy J M; Dicke, Marcel; van Loon, Joop J A

    2013-10-01

    The black currant-lettuce aphid, Nasonovia ribisnigri, is an important pest of cultivated lettuce, Lactuca sativa. Since 1982, the control of this aphid on lettuce is largely based on host plant resistance, conferred by the Nr gene, introgressed from Lactuca virosa. The resistance mechanism remains to be identified. N. ribisnigri populations virulent on the Nr-based resistance in lettuce have emerged in several locations in Europe since 2007. The objective of this study was to investigate the resistance mechanism mediated by the Nr gene in lettuce by detailed studies of aphid feeding behaviour and performance. Both avirulent (Nr:0) and virulent (Nr:1)biotypes of N. ribisnigri were studied on five resistant and two susceptible near isogenic lines (NILs). In addition, survival and colony development were quantified.Nr:0 aphids showed a strong decrease in sieve element ingestion and took longer to accept a sieve element on resistant NILs compared with susceptible NILs, and no aphids survived on the resistant NIL. Nr:1 aphids fed and performed equally well on the resistant and susceptible NILs. The resistance mechanism against Nr:0 aphids encoded by the Nr gene seems to be located in the phloem, although we also observed differences in feeding behaviour during the pathway phase to the phloem. Nr:1 aphids were highly virulent to the resistance conferred by the Nr gene. The consequences of the appearance of Nr:1 aphids for control of N. ribisnigri are discussed.

  15. Solar ultraviolet radiation affects the activity of ribulose-1, 5-bisphosphate carboxylase-oxygenase and the composition of photosynthetic and xanthophyll cycle pigments in the intertidal green alga Ulva lactuca L.

    NARCIS (Netherlands)

    Bischof, K; Krabs, G; Wiencke, C; Hanelt, D

    The effect of solar UV radiation on the physiology of the intertidal green macroalga Ulva lactuca L. was investigated. A natural Ulm community at the shore of Helgoland was covered with screening foils, excluding UV-B or UV-B + UV-A from the solar spectrum. In the sampled material, changes in the

  16. A Bayesian analysis of gene flow from crops to their wild relatives: cultivated (Lactuca sativa L.) and prickly lettuce (L. serriola L.) and the recent expansion of L. serriola in Europe

    NARCIS (Netherlands)

    Uwimana, B.; Andrea, D' L.; Felber, F.; Hooftman, D.A.P.; Nijs, den H.C.M.; Smulders, M.J.M.; Visser, R.G.F.; Wiel, van de C.C.M.

    2012-01-01

    Interspecific gene flow can lead to the formation of hybrid populations that have a competitive advantage over the parental populations, even for hybrids from a cross between crops and wild relatives. Wild prickly lettuce (Lactuca serriola) has recently expanded in Europe and hybridization with the

  17. sp sup 2 and sp sup 3 bonding configurations in low nitrogen content a-CN sub x thin films

    CERN Document Server

    Mezzasalma, A M; Neri, F; Trusso, S

    2003-01-01

    The results of an electron spectroscopy study carried out on a set of pulsed laser deposited CN sub x films are reported. A progressive degree of graphitization, deduced from the continuous increase in the sp sup 2 bond fraction, has been found for x values up to 25%. The mass density values, deduced by a proper treating of both the x-ray photoelectron spectroscopy and reflection electron energy loss spectroscopy data, are consistent with a material made up by two phases, namely a sp sup 2 threefold (graphite-like) and a sp sup 3 fourfold (diamond-like) coordinated one. The behaviour of the density of the samples as a function of the N content does not show any abrupt change in going from lower to higher nitrogen concentrations as found by other authors, this certainly being due to differences in the starting sp sup 3 /sp sup 2 ratio of the films at zero N concentration and to their different preparation parameters.

  18. Potencial alelopático de espécies nativas na germinação e crescimento inicial de Lactuca sativa L. (Asteraceae Allelopathic potential of native species in Lactuca sativa L. (Asteraceae germination and initial growth

    Directory of Open Access Journals (Sweden)

    Fabiana Maraschin-Silva

    2006-03-01

    Full Text Available A alelopatia caracteriza-se pelos efeitos danosos ou benéficos sobre o desenvolvimento da vegetação, causados por substâncias químicas produzidas e liberadas para o ambiente por uma planta. Com o objetivo de avaliar o potencial alelopático de espécies brasileiras, foram testados extratos foliares de Cecropia pachystachya Trec. (Urticaceae, Peltophorum dubium (Spreng. Taub. (Fabaceae, Psychotria leiocarpa Cham. & Schltdl (Rubiaceae, Sapium glandulatum (Vell. Pax (Euphorbiaceae e Sorocea bonplandii (Baill. Burg., Lanj. & Boer (Moraceae, utilizando-se bioensaios de germinação e crescimento e alface (Lactuca sativa L. como planta alvo. Nesses bioensaios, foram usados extratos foliares aquosos nas concentrações de 2 e 4%, preparados por maceração estática com água fria e quente. Os extratos das cinco espécies causaram atraso na germinação dos aquênios da alface, bem como efeitos tóxicos no crescimento das plântulas, com redução e enfraquecimento das raízes. Os resultados obtidos mostraram a presença de substâncias químicas inibidoras nos extratos, revelando potencial alelopático para as cinco espécies avaliadas.Allelopathy is characterized by harmful or beneficial effects on vegetation development, caused by chemical substances produced and released into the environment by the plant. Aiming to assess the allelopathic potential of Brazilian species, aqueous leaf extracts of Cecropia pachystachya Trec. (Urticaceae, Peltophorum dubium (Spreng. Taub. (Fabaceae, Psychotria leiocarpa Cham. & Schltdl (Rubiaceae, Sapium glandulatum (Vell. Pax (Euphorbiaceae, and Sorocea bonplandii (Baill. Burger, Lanj. & Boer (Moraceae were tested on lettuce using germination and growth bioassays. In these bioassays, aqueous leaf extracts were used at concentrations of 2 and 4%, prepared by static maceration with cold and hot water. The five species extracts delayed lettuce germination and produced toxic effects on seedling growth, with root

  19. Ultrastructural and developmental evidence of phytotoxicity on cos lettuce (Lactuca sativa) associated with nonylphenol exposure.

    Science.gov (United States)

    de Bruin, Willeke; van der Merwe, Chris; Kritzinger, Quenton; Bornman, Riana; Korsten, Lise

    2017-02-01

    It has long been understood that the presence of endocrine disrupter chemicals (EDCs) in water can affect the reproductive, behavioural and regulatory systems of different types of mammals. Thus far, only a handful of studies have examined its impact on plant systems. Present research is limited to the potential uptake of these chemicals by plants and the general phytotoxic effects it can elicit. The aim of this study was to determine what effect an EDC has on developing plant and cell organelles and how it affects it. In this study, cos lettuce plants were exposed to different concentrations of nonylphenol (NP), an EDC, in a static hydroponic system. Changes in plant morphology, mass and length, chlorophyll content, as well as electrolyte leakage were examined. Furthermore an in-depth investigation of the plant cell ultrastructure was carried out with transmission electron microscopy. Results indicated that cos lettuce growth was severely restricted, chlorophyll content was reduced, leakage of electrolytes increased and roots were stunted especially after ≥3200 μg/l NP exposures. The structure of the rough endoplasmic reticulum, vacuole and chloroplast were also changed. This study emphasizes the importance of water quality management, since the presence of an EDC, like NP, can negatively impact the yield and internal structure of one of the world's most significant salad crops, namely lettuce. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Modeling Electronic Properties of Complex Oxides

    Science.gov (United States)

    Krishnaswamy, Karthik

    Complex oxides are a class of materials that have recently emerged as potential candidates for electronic applications owing to their interesting electronic properties. The goal of this dissertation is to develop a fundamental understanding of these electronic properties using a combination of first-principles approaches based on density functional theory (DFT), and Schrodinger-Poisson (SP) simulation (Abstract shortened by ProQuest.

  1. An assessment of the role of ethylene in mediating lettuce (Lactuca sativa) root growth at high temperatures.

    Science.gov (United States)

    Qin, L; He, J; Lee, S K; Dodd, I C

    2007-01-01

    Growth of temperate lettuce (Lactuca sativa) plants aeroponically in tropical greenhouses under ambient root-zone temperatures (A-RZTs) exposes roots to temperatures of up to 40 degrees C during the middle of the day, and severely limits root and shoot growth. The role of ethylene in inhibiting growth was investigated with just-germinated (24-h-old) seedlings in vitro, and 10-d-old plants grown aeroponically. Compared with seedlings maintained at 20 degrees C, root elongation in vitro was inhibited by 39% and root diameter increased by 25% under a temperature regime (38 degrees C/24 degrees C for 7 h/17 h) that simulated A-RZT in the greenhouse. The effects on root elongation were partially alleviated by supplying the ethylene biosynthesis inhibitors aminooxyacetic acid (100-500 microM) or aminoisobutyric acid (5-100 microM) to the seedlings. Application of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid to seedlings grown at 20 degrees C mimicked the high temperature effects on root elongation (1 microM) and root diameter (1 mM). Compared with plants grown at a constant 20 degrees C root-zone temperature, A-RZT plants showed decreased stomatal conductance, leaf relative water content, photosynthetic CO(2) assimilation, shoot and root biomass, total root length, the number of root tips, and root surface area, but increased average root diameter. Addition of 10 microM ACC to the nutrient solution of plants grown at a constant 20 degrees C root-zone temperature mimicked the effects of A-RZT on these parameters but did not influence relative water content. Addition of 30 microM aminoisobutyric acid or 100 microM aminooxyacetic acid to the nutrient solution of A-RZT plants increased stomatal conductance and relative water content and decreased average root diameter, but had no effect on other root parameters or root and shoot biomass or photosynthetic CO(2) assimilation. Although ethylene is important in regulating root morphology and elongation at A

  2. Emergência e crescimento de alface (Lactuca sativa L. submetida a substratos orgânicos

    Directory of Open Access Journals (Sweden)

    Franciele Mara Lucca Zanardo Bohm

    2017-06-01

    Full Text Available A agricultura orgânica se destaca como modo de produção que consiste em um sistema sustentável. Um dos desafios desse método de cultivo é a produção de alimentos com qualidade em quantidades suficientes sem comprometer o meio ambiente. Objetivou-se analisar o efeito de substratos orgânicos na germinação e crescimento inicial de alface. O experimento foi conduzido em delineamento inteiramente casualizado com quatro tratamentos (substratos e duas repetições. Foram testados os substratos: composto de Sibipiruna, substrato comercial, composto de Sibipiruna com chorume e substrato comercial com chorume. O chorume foi obtido exclusivamente da decomposição de vegetais. Foi avaliado o efeito dos substratos pelo percentual de germinação, massa fresca, massa seca e comprimento da radícula. Pôde-se considerar que houve diferença significativa entre os tratamentos. As sementes, quando germinadas em substrato de Sibipiruna com chorume, apresentaram maior massa seca e comprimento de radícula. Com relação à massa fresca, os valores obtidos foram maiores quando o chorume foi adicionado a ambos os substratos. O chorume obtido da decomposição de vegetais aumentou a germinação e o crescimento inicial das plântulas.Emergence and growth of lettuce (Lactuca sativa L. submitted to organic substratesAbstract: Organic agriculture stands out as a mode of production consisting of a sustainable system. One of the challenges of this method of cultivation is the production of sufficient quality food in sufficient quantities without compromising the environment. The objective of this study was to analyze the effect of organic substrates on germination and initial lettuce growth. The experiment was conducted in a completely randomized design with four treatments (substrates and two replicates. The substrates were tested: Sibipiruna compound, commercial substrate, Sibipiruna compound with slurry and commercial slurry substrate. The manure was

  3. Dependence of plant biometrics of cutting lettuce (Lactuca sativa L. varietis on the concentration of microfertilizer Avatar-1

    Directory of Open Access Journals (Sweden)

    В. Б. Кутовенко

    2017-09-01

    Full Text Available Purpose. To investigate the variability of plant biometrics of cutting lettuce (Lactuca sativa L. varieties depending on the concentration of microfertilizer Avatar-1. Methods. Field study, biometric technique, comparative approach, statistical evaluation, generalization. Results. Dependence of the plant height, the diameter of the leaf rosette, the number of leaves per plant, the leaf area of plants on the concentration of microfertilizer Avatar-1 was defined. Investigations of cutting lettuce ‘Afitsyon’ and ‘Concord’ varieties by Dutch breeding were conducted in 2016–2017 in the collection sites of the department of vegetable growing in the scientific-experimental field  “Fruit and vegetable garden” of the National University of Life and Environmental Sciences of Ukraine. In order to determine dependence of plant biometrics of cutting lettuce varieties on the concentration of complex microfertilizer Avatar-1, the following scheme was used for the both varieties: variant 1 – water (control; variant 2 – 0,10% solution; variant 3 – 0,25% solution; variant 4 – 0,50% solution. Plants were treated with microfertilizer three times during the vegetative period. Alterations of plant biometrics of cutting lettuce ‘Afitsyon’ and ‘Concord’ varieties  depending on the concentration of complex microfertilizer Avatar-1 was studied. Conclusions. It was found that in case of three-time plant treatment with complex microfertilizer Avatar-1 at the time of harvesting, the best plant biometrics was registered in variant 3 (concentration 0,25% for the both ‘Afitsyon’ and ‘Concord’ varie­ties of cutting lettuce. The height of plants of the cutting lettuce in ‘Afitsyon’ variety exceeded this figure in ‘Concord variety by 1,1–1,4 cm. The concentration of microfertilizer had no significant effect on the diameter of the leaf rosette of ‘Concord’ variety (25,1–25,9 см. The diame­ter of the leaf rosette of

  4. Remote sensing of nutrient deficiency in Lactuca sativa using neural networks for terrestrial and advanced life support applications

    Science.gov (United States)

    Sears, Edie Seldon

    2000-12-01

    A remote sensing study using reflectance and fluorescence spectra of hydroponically grown Lactuca sativa (lettuce) canopies was conducted. An optical receiver was designed and constructed to interface with a commercial fiber optic spectrometer for data acquisition. Optical parameters were varied to determine effects of field of view and distance to target on vegetation stress assessment over the test plant growth cycle. Feedforward backpropagation neural networks (NN) were implemented to predict the presence of canopy stress. Effects of spatial and spectral resolutions on stress predictions of the neural network were also examined. Visual inspection and fresh mass values failed to differentiate among controls, plants cultivated with 25% of the recommended concentration of phosphorous (P), and those cultivated with 25% nitrogen (N) based on fresh mass and visual inspection. The NN's were trained on input vectors created using reflectance and test day, fluorescence and test day, and reflectance, fluorescence, and test day. Four networks were created representing four levels of spectral resolution: 100-nm NN, 10-nm NN, 1-nm NN, and 0.1-nm NN. The 10-nm resolution was found to be sufficient for classifying extreme nitrogen deficiency in freestanding hydroponic lettuce. As a result of leaf angle and canopy structure broadband scattering intensity in the 700-nm to 1000-nm range was found to be the most useful portion of the spectrum in this study. More subtle effects of "greenness" and fluorescence emission were believed to be obscured by canopy structure and leaf orientation. As field of view was not as found to be as significant as originally believed, systems implementing higher repetitions over more uniformly oriented, i.e. smaller, flatter, target areas would provide for more discernible neural network input vectors. It is believed that this technique holds considerable promise for early detection of extreme nitrogen deficiency. Further research is recommended using

  5. Health risks resulting from contaminants transfers in soil-plants systems: case study of Atrazine in Lactuca sativa.

    Science.gov (United States)

    Mathieu, Camoin

    2015-04-01

    Food safety is presently at the center of great part of scientific and political debates. This represents a field of study in its own right of health risks, including ingestion by humans of hazardous biological, physical, chemical or radiological substances, from contaminated foods during different stages of production. Plant cultivation step is often one of the main sources of contamination, whether of voluntary (pesticide application) or accidental (nuclear, industrial waste, etc.) origin. As a result, the plants growth in an contaminated environment may increase the risk of transfer within the plant, and finally the exposure of humans. Furthermore, pesticides are among the main contaminants investigated in the frame of human health risks resulting from food intakes. However, most of these scientific works focus mainly on their occurrence and persistence in water bodies, and few of them are interested in soil/plants transfer. In this context, the understanding of the processes governing transfers of pesticides in plants is become a necessity, in particular to prevent human risks linked the ingestion of food produced in contaminated environments. This objective can be reached by studying the pollutants behavior in soils/plants transfers, and using various substances/plants couples. In our study, we selected a salad/pesticide couple as our experimental model. Atrazine was chosen as model contaminant because of its problematic presence in a large amount of environmental compartments, its physico-chemical properties and because of its long-term toxicity. Lactuca sativa has been selected as model plant because of its importance in French agriculture, and specifically in Languedoc-Roussillon. Salad has been cultivated in peats and irrigated with an atrazine spiked water solution (concentrations from 10 to 100 μg/L). Plant growth in such conditions has been compared to a growth in clean condition (irrigation with non spiked water). Measurements of atrazine contents in

  6. Toxic effects of imidazolium ionic liquids on the green seaweed Ulva lactuca: oxidative stress and DNA damage.

    Science.gov (United States)

    Kumar, Manoj; Trivedi, Nitin; Reddy, C R K; Jha, Bhavanath

    2011-11-21

    The green credentials of ionic liquids (ILs) are being increasingly questioned due to the growing evidence of their toxicity to aquatic ecosystems, although the mechanisms of toxicity are unknown. This study provides insights into the mechanism of toxicity and biological effects of 1-alkyl-3-methylimidazolium bromide [C(n)mim]Br (n = 4 to 16) on the marine macroalga Ulva lactuca. The cell viability of this alga during IL exposure was found to be negatively correlated to the chain length of the alkyl group. The IL ([C(12)mim]Br) exposure triggers the generation of reactive oxygen species (ROS viz. O(2)(•-), H(2)O(2), and OH(•)), damage of the membrane and DNA, and inhibition of antioxidant systems in the alga. The enhanced production of ROS and lipid peroxidation in the alga subjected to LC(50) concentration for 4 days was largely attributed to lipoxygenase (LOX) activity coupled with the induction of two LOX isoforms (~80 kDa and ~55 kDa). Pretreatment of the algal thallus with enzyme inhibitors such as diphenylene iodonium, sodium azide, cantharidin, and oxadiazoloquinoxalin-1-one, prior to [C(12)mim]Br exposure showed the regulation of ROS by the activation of membrane bound NADPH-oxidase and cytochrome oxidase. The IL exposure resulted in the accumulation of n-3 and n-6 fatty acids at 0.5 LC(50) concentration indicating the induction of desaturase enzymes. Furthermore, antioxidant enzyme activities such as superoxide dismutase (SOD), ascorbate peroxidase (APX), and glutathione reductase (GR) were enhanced by 1.3-2.0-fold, while glutathione peroxidase (GSH-Px) diminished, together with a higher regeneration rate of reduced ascorbate and glutathione. The isoforms of antioxidant enzymes, namely, Mn-SOD (~85 kDa), APX (~125 and 45 kDa), and GR (~135 kDa) regulated differentially to IL exposure. The comet assay performed for the first time for seaweeds revealed the significant induction of DNA damage (>50-70% increase in % tail DNA over control) in alga exposed

  7. Bradysia sp. em morangueiro Bradysia sp. in strawberry

    Directory of Open Access Journals (Sweden)

    Bernadete Radin

    2009-04-01

    Full Text Available No trabalho, relatam-se os primeiros registros de Bradysia sp. (Insecta: Diptera: Sciaridae em morangueiro (Fragaria x ananassa Duch., cultivado no Município de Eldorado do Sul, RS. O cultivo foi realizado em sacolas com três metros de comprimento, preenchidas com substrato composto de casca de arroz e turfa, dispostas horizontalmente sobre bancadas de madeira, em ambiente protegido. A presença de Bradysia sp. foi observada na segunda quinzena de agosto de 2005. Neste trabalho, estão descritos os sintomas apresentados no morangueiro pela praga, prováveis conseqüências sobre o aparecimento de doenças e uma breve descrição morfológica da Bradysia sp., adulto e fase larval.This paper describes the first record of Bradysia sp. (Insecta; Diptera; Sciaridae in strawberry (Fragaria x ananassa, cultivated in the city of Eldorado do Sul, RS, Brazil. Strawberry was planted in plastic bags filled with a mixture of burnt rice hulls and peat and cultivated in a greenhouse. The presence of Bradysia sp was noticed in the second fortnight of August, 2005. The symptoms in strawberry and the probable consequences in terms of disease arising were described in the present study, as well as the morphological characterization of Bradysia sp. and its illustrations.

  8. SP-100 reactor design

    International Nuclear Information System (INIS)

    Armijo, J.S.; Atwell, J.; Pluta, P.R.; Smith, M.A.; Solorzano, E.R.

    1987-01-01

    The SP-100 space reactor power system is being designed and developed as part of the Ground Engineering System (GES) contract between General Electric Company as the system developer and the Department of Energy. Other key participants in the GES program include Westinghouse Hanford Company (site operator), Los Alamos National Laboratory (fuel development and production), Oak Ridge National Laboratory (materials), and Westinghouse, Advanced Energy Systems Division (shield, HTS equipment). The GES Program includes two major elements. First, the development of a Reference Flight System design at 100 kWe output to the user, and second the validation of the Reference Flight System design by analysis and by testing. Development of key technologies along with component and system testing is an essential part of the validation program. The nuclear subsystem validation includes the design, manufacture, assembly and operational testing of a Ground Reactor Test Assembly. The subject of this paper is the reactor design for the Reference Flight System. The reference flight design is in the preliminary design stage and will evolve over the next year

  9. Molecular Phylogeny and Surface Morphology of Thiriotia hyperdolphinae n. sp. and Cephaloidophora oradareae n. sp. (Gregarinasina, Apicomplexa) Isolated from a Deep Sea Oradarea sp. (Amphipoda) in the West Pacific.

    Science.gov (United States)

    Wakeman, Kevin C; Yabuki, Akinori; Fujikura, Katsunori; Tomikawa, Ko; Horiguchi, Takeo

    2017-10-17

    In an effort to broaden our understanding of the biodiversity and distribution of gregarines infecting crustaceans, this study describes two new species of gregarines, Thiriotia hyperdolphinae n. sp. and Cephaloidophora oradareae n. sp., parasitizing a deep sea amphipod (Oradarea sp.). Amphipods were collected using the ROV Hyper-Dolphin at a depth of 855 m while on a cruise in Sagami Bay, Japan. Gregarine trophozoites and gamonts were isolated from the gut of the amphipod and studied with light and scanning electron microscopy, and phylogenetic analysis of 18S rDNA. Thiriotia hyperdolphinae n. sp. was distinguished from existing species based on morphology, phylogenetic position, as well as host niche and geographic locality. Cephaloidophora oradareae n. sp. distinguished itself from existing Cephaloidophora, based on a difference in host (Oradarea sp.), geographic location, and to a certain extent morphology. We established this latter new species with the understanding that a more comprehensive examination of diversity at the molecular level is necessary within Cephaloidophora. Results from the 18S rDNA molecular phylogeny showed that T. hyperdolphinae n. sp. was positioned within a clade consisting of Thiriotia spp., while C. oradareae n. sp. grouped within the Cephaloidophoridae. Still, supplemental genetic information from gregarines infecting crustaceans will be needed to better understand relationships within this group of apicomplexans. © 2017 The Author(s) Journal of Eukaryotic Microbiology © 2017 International Society of Protistologists.

  10. Enzymatic regulation of photosynthetic and light-independent carbon fixation in Laminaria setchellii (Phaeophyta, Ulva lactuca (Chlorophyta and Iridaea cordata (Rhodophyta Regulación enzimática de la fotosíntesis y la fijación de carbono en obscuridad por Laminaria setchellii (Phaeophyta, Ulva lactuca (Chlorophyta e Iridaea cordata (Rhodophyta

    Directory of Open Access Journals (Sweden)

    ALEJANDRO CABELLO-PASINI

    2001-06-01

    Full Text Available Carbon is acquired through photosynthetic and non-photosynthetic processes in marine algae. However, little is known about the biochemical regulation of these metabolic pathways along the thallus of seaweeds. Consequently, the objective of this study was to assess the distribution of in vivo carboxylation pathways and to relate them to the in vitro activity of ribulose 1,5-bisphosphate carboxylase/oxygenase (RUBISCO, phosphoenolpyruvate carboxykinase (PEPCK, and phosphoenolpyruvate carboxylase (PEPC in the Phaeophyte Laminaria setchellii, the Chlorophyte Ulva lactuca, and the Rhodophyte Iridaea cordata. Chlorophyll-a levels did not vary in U. lactuca and I. cordata. However, pigment levels were significantly lower in the meristematic region of L. setchellii probably as a result of a lack of differentiation of the chloroplasts in this region. Similarly, net photosynthesis did not vary in the thallus of U. lactuca and I. cordata, while it increased from the stipe and meristem towards the lamina of L. setchellii. In contrast to photosynthesis, light-independent carbon fixation rates were significantly greater in the meristematic region of L. setchellii suggesting a compensating mechanism for carbon incorporation in photosynthetically limited tissue. The activity of RUBISCO and PEPCK followed a pattern similar to that of in vivo carboxylation processes indicating that in vivo carbon assimilation is regulated by the activity of the carboxylating enzymes throughout the thallus of L. setchelliiLa incorporación de carbono en algas marinas se lleva a cabo mediante procesos fotosintéticos y no-fotosintéticos. Sin embargo, poco se sabe sobre la regulación bioquímica de estas rutas metabólicas en el tejido de algas marinas. En consecuencia, el objetivo de este estudio fue el de evaluar la distribución de la carboxilación in vivo y relacionarlas a la actividad in vitro de ribulosa 1,5-bisfosfato carboxilasa/oxigenasa (RUBISCO, fosfoenolpiruvato

  11. Influência alelopática de hortelã (Mentha x villosa Huds. sobre emergência de plântulas de alface (Lactuca sativa L. Allelopathic influence of mint (Mentha x villosa Huds. on the emergence of lettuce (Lactuca sativa L. seedlings

    Directory of Open Access Journals (Sweden)

    J.T.L.S. Maia

    2011-01-01

    Full Text Available Objetivou-se com esse trabalho avaliar a interferência de possíveis efeitos alelopáticos de Mentha x villosa Huds. sobre a emergência de Lactuca sativa L. As atividades foram conduzidas em laboratório, no Instituto de Ciências Agrárias (ICA da Universidade Federal de Minas Gerais, em Montes Claros/MG. Foram propostos três tratamentos, sendo esses: solo A, coletado em área cultivada com hortelã no horto medicinal do ICA/UFMG; solo B, coletado em áreas adjacentes e, testemunha (papel germiteste.O delineamento experimental foi inteiramente casualizado (DIC, com sete repetições. As variáveis avaliadas foram: porcentagem e índice de velocidade de emergência. Observou-se que a emergência de plântulas de Lactuca sativa foi significativamente afetada pelo solo A (6,95% se comparada com o solo B (21,71%, representando assim, uma inibição da emergência, ou seja, efeito alelopático da hortelã sobre a emergência de alface. Já o índice de velocidade de emergência (IVE não diferiu significativamente entre os solos testados.This study aimed to assess the interference of possible allelopathic effects of Mentha x villosa Huds. on the germination of Lactuca sativa L. The activities were carried out in laboratory, at the Institute of Agricultural Sciences (ICA of the Federal University of Minas Gerais, Montes Claros, Minas Gerais State, Brazil. The following three treatments were proposed: soil A, collected in area cultivated with mint at the garden of ICA; soil B, collected in adjacent areas; and control (germitest paper. Experimental design was completely randomized (CR, with seven replicates. The evaluated variables were: germination percentage and speed index. The emergence of Lactuca sativa seedlings was significantly affected by soil A (6.95% when compared to soil B (21.71%, indicating thus emergence inhibition, i.e. an allelopathic effect of mint on lettuce emergence. On the other hand, the germination speed index (GSI did not

  12. Electronics and electronic systems

    CERN Document Server

    Olsen, George H

    1987-01-01

    Electronics and Electronic Systems explores the significant developments in the field of electronics and electronic devices. This book is organized into three parts encompassing 11 chapters that discuss the fundamental circuit theory and the principles of analog and digital electronics. This book deals first with the passive components of electronic systems, such as resistors, capacitors, and inductors. These topics are followed by a discussion on the analysis of electronic circuits, which involves three ways, namely, the actual circuit, graphical techniques, and rule of thumb. The remaining p

  13. Controle de Rhizoctonia solani e Fusarium oxysporum f.sp. phaseoli por biopreparados de isolados de Trichoderma spp.

    Directory of Open Access Journals (Sweden)

    Pedro Paulo Dias

    2013-12-01

    Full Text Available Os experimentos objetivaram avaliar em condições de casa de vegetação o biocontrole dos fitopatógenos Rhizoctonia solani (RS e Fusarium oxysporum f.sp. phaseoli (FOP em alface (Lactuca sativa L. cultivar Regina, e feijão-vagem (Phaseolus vulgaris L. cultivar Alessa, respectivamente, utilizando como agentes antagonistas, 10 isolados de Trichoderma spp. selecionados em testes in vitro. Foram feitos biopreparados à base de arroz previamente colonizado por isolados de Trichoderma spp. e posteriormente triturados. Para a realização dos testes, os biopreparados foram inoculados previamente na proporção de 10(9 conídios.mL-1, em substrato comercial para produção de mudas. Após sete dias, os patógenos foram introduzidos separadamente em duas concentrações distintas: R. solani na proporção de 144 mg de meio de arroz por kg de substrato e F. oxysporum f.sp. phaseoli inoculado na forma de suspensão contendo 4,75 x 10(6 conídios.mL-1. Avaliou-se a influência dos biopreparados na % de damping-off de pós-emergência em plantas de alface e a severidade de murcha em plantas de feijão-vagem. O biopreparado referente ao isolado T-03 foi o mais eficiente no controle de R. solani em plantas de alface cultivar Regina, por ter reduzido a incidência de damping-off de pós-emergência nessa cultura. Por outro lado, nenhum dos biopreparados apresentou efeito antagonista satisfatório à F. oxysporum f.sp. phaseoli em plantas de feijão-vagem.

  14. Penicillium araracuarense sp. nov., Penicillium elleniae sp. nov., Penicillium penarojense sp. nov., Penicillium vanderhammenii sp. nov. and Penicillium wotroi sp. nov., isolated from leaf litter

    DEFF Research Database (Denmark)

    Houbraken, Jos; López-Quintero, Carlos A.; Frisvad, Jens Christian

    2011-01-01

    Several species of the genus Penicillium were isolated during a survey of the mycobiota of leaf litter and soil in Colombian Amazon forest. Five species, Penicillium penarojense sp. nov. (type strain CBS 113178T = IBT 23262T), Penicillium wotroi sp. nov. (type strain CBS 118171T = IBT 23253T......), Penicillium araracuarense sp. nov. (type strain CBS 113149T = IBT 23247T), Penicillium elleniae sp. nov. (type strain CBS 118135T = IBT 23229T) and Penicillium vanderhammenii sp. nov. (type strain CBS 126216T = IBT 23203T) are described here as novel species. Their taxonomic novelty was determined using......, andrastin A, pulvilloric acid, paxillin, paspaline and janthitrem, were commonly produced by these phylogenetically related species. The novel species had a high growth rate on agar media, but could be distinguished from each other by several macro- and microscopical characteristics....

  15. Uji Fitokimia, Kandungan Total Fenol dan Aktivitas Antioksidan Mikroalga Spirulina sp., Chlorella sp., dan Nannochloropsis sp.

    Directory of Open Access Journals (Sweden)

    Diini Fithriani

    2015-12-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui kandungan fitokimia, total fenol, dan aktivitas antioksidan dari mikroalga Spirulina sp., Nannochloropsis sp., dan Chlorella sp. Mikroalga diekstrak dengan ekstraksi tunggal menggunakan etanol. Skrining fitokimia dilakukan secara kualitatif. Analisis total fenol dilakukan secara spektrofotometri dengan metode Folin-Ciocalteu. Analisis antioksidan dilakukan dengan metode 2,2-diphenyl-1-picrylhydrazyl (DPPH dan Ferric Reducing Antioxidant Power (FRAP. Skrining fitokimia menunjukkan keberadaan tanin, flavonoid, steroid, glikosida, dan alkaloid pada ekstrak etanol ketiga jenis mikroalga, sedangkan saponin hanya terdeteksi pada ekstrak etanol Spirulina sp. dan Chlorella sp., adapun triterpenoid tidak terdeteksi pada ekstrak etanol ketiga jenis mikroalga. Hasil penelitian menunjukkan bahwa kandungan total fenol, aktivitas antioksidan (IC50, dan kapasitas antioksidan (FRAP tertinggi diperoleh pada ekstrak etanol Spirulina sp. dengan nilai berturut turut sebesar 0,32 ± 0,025 mg GAE g-1D.W., 518,94 ppm, dan  49,95 ± 2,02 (mmol Fe2+ eq.g-1D.W. Dalam penelitian ini diketahui bahwa kandungan fenol total memiliki korelasi  yang kuat  dengan kapasitas antioksidan metode FRAP (R2= 0,84, dan aktivitas antioksidan metode DPPH (R2= 0,79.

  16. Uji Fitokimia, Kandungan Total Fenol Dan Aktivitas Antioksidan Mikroalga Spirulina Sp., Chlorella Sp., dan Nannochloropsis Sp.

    Directory of Open Access Journals (Sweden)

    Diini Fithriani

    2015-12-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui kandungan fitokimia, total fenol, dan aktivitas antioksidan dari mikroalga Spirulina sp., Nannochloropsis sp., dan Chlorella sp. Mikroalga diekstrak dengan ekstraksi tunggal menggunakan etanol. Skrining fitokimia dilakukan secara kualitatif. Analisis total fenol dilakukan secara spektrofotometri dengan metode Folin-Ciocalteu. Analisis antioksidan dilakukan dengan metode 2,2-diphenyl-1-picrylhydrazyl (DPPH dan Ferric Reducing Antioxidant Power (FRAP. Skrining fitokimia menunjukkan keberadaan tanin, flavonoid, steroid, glikosida, dan alkaloid pada ekstrak etanol ketiga jenis mikroalga, sedangkan saponin hanya terdeteksi pada ekstrak etanol Spirulina sp. dan Chlorella sp., adapun triterpenoid tidak terdeteksi pada ekstrak etanol ketiga jenis mikroalga. Hasil penelitian menunjukkan bahwa kandungan total fenol, aktivitas antioksidan (IC50, dan kapasitas antioksidan (FRAP tertinggi diperoleh pada ekstrak etanol Spirulina sp. dengan nilai berturut turut sebesar 0,32 ± 0,025 mg GAE g-1D.W., 518,94 ppm, dan  49,95 ± 2,02 (mmol Fe2+ eq.g-1D.W. Dalam penelitian ini diketahui bahwa kandungan fenol total memiliki korelasi  yang kuat  dengan kapasitas antioksidan metode FRAP (R2= 0,84, dan aktivitas antioksidan metode DPPH (R2= 0,79.

  17. Root adaptation and ion selectivity affects the nutritional value of salt-stressed hydroponically grown baby-leaf Nasturtium officinale and Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Juan A. Fernández

    2016-12-01

    Full Text Available The response of watercress (Nasturtium officinale L. to salinity has been scarcely addressed in literature despite its growing importance in the baby-leaf market and its wide cultivation in salt-affected agricultural regions. This work evaluates the effect of salinity (2.5, 5 and 10 dS m-1 on productive and quality features of watercress compared with another crop widely cultivated for the baby-leaf sector (lettuce, Lactuca sativa. In watercress, a linear relationship (R2=0.75 was observed between yield decrease and Cl– accumulation in leaves, whereas yield was not affected by salinity in lettuce. NaCl application increased Na+ accumulation at the expense of Ca2+ uptake in the leaf tissues of both crops, but also of K+ in watercress. Health-related features were improved by salinity (e.g. increased phenolics and reduced nitrates, especially in watercress, with limited sensorial quality evaluation effects.

  18. 4,4,4-trifluoro-3-(indole-3-)butyric acid promotes root elongation in Lactuca sativa independent of ethylene synthesis and pH

    Science.gov (United States)

    Zhang, Nenggang; Hasenstein, Karl H.

    2002-01-01

    We studied the mode of action of 4,4,4-trifluoro-3- (indole-3-) butyric acid (TFIBA), a recently described root growth stimulator, on primary root growth of Lactuca sativa L. seedlings. TFIBA (100 micromoles) promoted elongation of primary roots by 40% in 72 h but inhibited hypocotyl growth by 35%. TFIBA induced root growth was independent of pH. TFIBA did not affect ethylene production, but reduced the inhibitory effect of ethylene on root elongation. TFIBA promoted root growth even in the presence of the ethylene biosynthesis inhibitor L-alpha-(2-aminoethoxyvinyl)glycine. TFIBA and the ethylene-binding inhibitor silver thiosulphate (STS) had a similar effect on root elongation. The results indicate that TFIBA-stimulated root elongation was neither pH-dependent nor related to inhibition of ethylene synthesis, but was possibly related to ethylene action.

  19. Allelopathic Activity of Extracts from Different Brazilian Peanut (Arachis hypogaeaL.) Cultivars on Lettuce(Lactuca sativa)and Weed Plants.

    Science.gov (United States)

    Casimiro, G S; Mansur, E; Pacheco, G; Garcia, R; Leal, I C R; Simas, N K

    2017-01-01

    Peanut ( Arachis hypogaea L.) is the fourth most consumed oleaginous plant in the world, producing seeds with high contents of lipids, proteins, vitamins, and carbohydrates. Biological activities of different extracts of this species have already been evaluated by many researchers, including antioxidant, antitumoral, and antibacterial. In this work, the allelopathic activity of extracts from different Brazilian peanut cultivars against lettuce (Lactuca sativa) and two weed plants ( Commelina benghalensis and Ipomoea nil ) was studied. Aerial parts, roots, seeds, and seed coats were used for the preparation of crude extracts. Seed extract partitioning was performed with n -hexane, dichloromethane, ethyl acetate, n -butanol, and aqueous residue. Germination and growth of hypocotyls and rootlets were evaluated after one and five days of incubation with plant extracts, respectively. Crude seed extract and its dichloromethanic partition displayed highest allelopathic activity. These results contribute for the study of new potential natural herbicides.

  20. Polyhydroxybutyrate by Streptomyces sp.: Production and characterization.

    Science.gov (United States)

    Krishnan, Sivakumar; Chinnadurai, Gandhi Shree; Perumal, Palani

    2017-11-01

    A total number of 20 actinomycetes isolates were isolated from soil sediments obtained from Semmancheri coastal areas of Bay of Bengal, India and they were qualitatively screened for the production of polyhydroxybutyrate (PHB) on a medium containing Sudan black stain. Nine of the 20 isolates produced PHB and the quantity of PHB produced varied from 1.79 to 4.26g -L . Among the positive isolates an actinomycete isolate which was identified as Streptomyces sp. through 16S rRNA sequencing analysis (Accession No: KF667247) produced relatively higher PHB than other positive isolates. Subsequently, the growth conditions were optimized for the maximum PHB production by the chosen organism. Attempt was also made to utilize natural carbon sources such as paddy straw, wheat bran, rice bran, sugarcane molasses and oil cake for the production of PHB in an attempt to reduce the cost production of PHB. The purified PHB was analyzed by Solid-State 13 C NMR, Fourier Transformed Infrared spectroscopy, Powder X-ray diffraction, Thermogravimetric Analysis, Scanning and Transmission Electron Microscopic analyses to determine the structure, crystallinity, purity and thermal stability. The present investigation has revealed that Streptomyces sp. could be a potential source for the production of PHB with desirable characteristics and could also be exploited for the industrial production. Copyright © 2017. Published by Elsevier B.V.

  1. Accumulation of heavy metals by lettuce (lactuca sativa l.) irrigated with different levels of wastewater of Quetta City

    International Nuclear Information System (INIS)

    Achakzai, A.K.K.

    2011-01-01

    Heavy metal contamination of soils resulting from irrigation by wastewater is causing major concern due to the potential health risk involved. This study was therefore designed to investigate the heavy metal ions viz., Cu/sup 2/sup +/, Fe/sup 2+/, Mn/sup 2+/, Zn/sup 2+/, Pb/sup 2+/, Ni/sup 2+ and Cd/sup 2+/ concentrations by lettuce (Lactuca sativa L.) grown in pots. This leafy vegetable was irrigated with 5 different concentrations of wastewater collected from 3 different localities viz., Chiltan town, Chiltan Ghee Mill (oil industry) and Zarghoon town of Quetta city. Tap water was used as background water. Plant samples were analyzed for their heavy metal contents using Atomic Absorption Spectroscopy (AAS). Results showed that localities, treatments and their interactions (except Cu/sup 2+/ and Pb/sup 2+/) generally exhibited highly significant (P=0.01) influence on the accumulation of heavy metals. The maximum values of 9.71; 509.06; 32.47; 94.38; 8.58; 5.05 and 7.45 mg kg/sup -1/ for Cu/sup 2+/, total Fe/sup 2+/, Mn/sup 2+/, Zn/sup 2+/, Ni/sup 2+/,Pb/sup 2+/, and Cd/sup 2+/ respectively, were generally obtained in highest concentration of effluents. While maximum values of 9.02; 4.47 and 7.90 mg kg-1 of Cu/sup 2+/, Ni/sup 2+/ and Cd/sup 2+/ were obtained for Chiltan ghee mill effluents. However, maximum values i.e., 435.96 and 80.47 mg kg-1 of total Fe and Zn/sup 2+/ were recorded for Chiltan town. The highest values of 30.09 and 6.32 mg kg-1 for Mn/sup 2+/ and Pb/sup 2+/ were noted in Zarghoon town, respectively. On the basis of grand mean values,the magnitude of heavy metals detected for various metals is in order: Fe > Zn >Mn> Cu >Pb> Cd > Ni. Results further demonstrated that the total concentrations of Cu/sup 2+/, Fe/sup 2+/, Mn/sup 2+/, Zn/sup 2+/ and Ni/sup 2+/ are within the recommended international standards set by WHO/FAO, but could be reached to toxic level either by the consecutive use of effluents or by increased dietary pattern of the consumers

  2. Fully substituted unsaturated lactones from endophytic Myrothecium sp.

    Science.gov (United States)

    Xu, Hao; Jiang, Nan; Guo, Ye; Jiao, Rui-Hua; Cui, Jiang-Tao; Song, Yong-Chun; Tan, Ren-Xiang

    2011-10-01

    Two new α,β-unsaturated γ-lactones, myrolactones A (1) and B (2), were characterized from the culture broth of the Myrothecium sp. IFB-E106 isolated from the roots of Vatica mangachapoi Blauco. The absolute configuration was determined by the computational electronic circular dichroism approach. Myolactone B showed neuraminidase inhibitory activity with the IC(50) value of 13.95 μM.

  3. Estudo da ocorrência de enteroparasitas em hortaliças comercializadas na região metropolitana de São Paulo, SP, Brasil: I - Pesquisa de helmintos Study on the occurrence of intestinal parasites on vegetables commercially traded in the metropolitan area of S.Paulo, SP, Brazil: I - Search for helminths

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Fernandes de Oliveira

    1992-08-01

    Full Text Available Hortaliças in natura, comercializadas na região metropolitana de São Paulo, SP (Brasil, foram analisadas através de metodologia própria, visando à pesquisa e à identificação de formas de transmissão de helmintos intestinais de interesse médico. As hortaliças examinadas, constituídas de 50 amostras de cada variedade, foram de: alface (Lactuca sativa, variedades lisa e crespa, escarola (Chichorium sp e agrião (Nasturtium officinale. Os resultados evidenciaram elevados percentuais de contaminação em todas as variedades analisadas, porém, as freqüências de helmintos foram maiores no agrião. A escarola apresentou valores médios, geralmente situados entre as alfaces e o agrião. Os números médios de ovos e larvas por 100 gramas de amostra, embora elevados, não apresentaram diferenças estatisticamente significantes entre as quatro variedades de hortaliças estudadas. Uma grande variedade de helmintos, de ocorrência freqüente na população residente na Região Metropolitana de São Paulo, foi observada nas amostras. Os mais freqüentes, no entanto, foram: ancilostomídeos e Ascaris sp. Recuperaram-se também ovos de Toxocara sp, Fasciola sp e de tricostrongilídeos, comprovando a ocorrência de contaminação das hortaliças por fezes de animais domésticos. Considerando-se os resultados obtidos, ressalta-se a importância das hortaliças na transmissão de helmintíases intestinais, bem como a necessidade de medidas que propiciem uma melhoria na qualidade higiênico-sanitária destes alimentos.Vegetables in natura, commercially traded in the metropolitan area of S. Paulo, were analysed by the appropriate methodology with a view to discovering an identifying the paths of transmission of enteroparasites of medical interest. The vegetables under study consisted of 50 samples of each variety listed below: lettuce (Lactuca sativa -oily leaves and crisphead varieties, endive (Chicorium sp and water-cress (Nasturtium Officinale

  4. Sticholonche zanclea (Protozoa, Actinopoda in fecal pellets of copepods and Euphausia sp. in Brazilian coastal waters

    Directory of Open Access Journals (Sweden)

    E. M. Eskinazi-Sant'Anna

    Full Text Available Fecal pellets produced by mesozooplanktonic copepods (Centropages velificatus and Paracalanus parvus and macrozooplanktonic Euphausiacea (Euphausia sp. were examined using scanning electron microscopy. Fragments of the protozoan Sticholonche zanclea were found in both copepod and in Euphausia sp. fecal pellets, even when the abundance of the protozoan in the water was low. The results suggest that S. zanclea is an important food resource for different trophic levels, including meso- and macrozooplankton, in Brazilian coastal waters.

  5. Lactobacillus apinorum sp. nov., Lactobacillus mellifer sp. nov., Lactobacillus mellis sp. nov., Lactobacillus melliventris sp. nov., Lactobacillus kimbladii sp. nov., Lactobacillus helsingborgensis sp. nov. and Lactobacillus kullabergensis sp. nov., isolated from the honey stomach of the honeybee Apis mellifera

    Science.gov (United States)

    Alsterfjord, Magnus; Nilson, Bo; Butler, Èile; Vásquez, Alejandra

    2014-01-01

    We previously discovered a symbiotic lactic acid bacterial (LAB) microbiota in the honey stomach of the honeybee Apis mellifera. The microbiota was composed of several phylotypes of Bifidobacterium and Lactobacillus. 16S rRNA gene sequence analyses and phenotypic and genetic characteristics revealed that the phylotypes isolated represent seven novel species. One grouped with Lactobacillus kunkeei and the others belong to the Lactobacillus buchneri and Lactobacillus delbrueckiisubgroups of Lactobacillus. We propose the names Lactobacillus apinorum sp. nov., Lactobacillus mellifer sp. nov., Lactobacillus mellis sp. nov., Lactobacillus melliventris sp. nov., Lactobacillus kimbladii sp. nov., Lactobacillus helsingborgensis sp. nov. and Lactobacillus kullabergensis sp. nov. for these novel species, with the respective type strains being Fhon13NT ( = DSM 26257T = CCUG 63287T), Bin4NT ( = DSM 26254T = CCUG 63291T), Hon2NT ( = DSM 26255T = CCUG 63289T), Hma8NT ( = DSM 26256T = CCUG 63629T), Hma2NT ( = DSM 26263T = CCUG 63633T), Bma5NT ( = DSM 26265T = CCUG 63301T) and Biut2NT ( = DSM 26262T = CCUG 63631T). PMID:24944337

  6. Ecdysteroids from a Zoanthus sp.

    Science.gov (United States)

    Suksamrarn, Apichart; Jankam, Aroon; Tarnchompoo, Bongkoch; Putchakarn, Sumaitt

    2002-08-01

    A new ecdysteroid, zoanthusterone, has been isolated from a marine zoanthid, Zoanthus sp. Ten known ecdysteroids, ponasterone A, 20-hydroxyecdysone 2-acetate, viticosterone E, integristerone A 25-acetate, 2-deoxy-20-hydroxyecdysone, ecdysone, ajugasterone C, dacryhainansterone, inokosterone, and 20-hydroxyecdysone, have also been isolated. This is the first report of ecdysteroids in a Zoanthus species.

  7. Sporulation of Cyclospora sp. oocysts.

    OpenAIRE

    Smith, H V; Paton, C A; Mitambo, M M; Girdwood, R W

    1997-01-01

    Cyclospora sp. oocysts sporulated maximally at 22 and 30 degrees C for 14 days retarded sporulation. Up to 12% of human- and baboon-derived oocysts previously stored at 4 degrees C for 1 to 2 months sporulated when stored for 6 to 7 days at 30 degrees C.

  8. Polyhydroxybutyrate particles in Synechocystis sp PCC 6803: facts and fiction

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, TK; Roberson, RW; Vermaas, WFJ

    2013-09-20

    Transmission electron microscopy has been used to identify poly-3-hydroxybutyrate (PHB) granules in cyanobacteria for over 40 years. Spherical inclusions inside the cell that are electron-transparent and/or slightly electron-dense and that are found in transmission electron micrographs of cyanobacteria are generally assumed to be PHB granules. The aim of this study was to test this assumption in different strains of the cyanobacterium Synechocystis sp. PCC 6803. Inclusions that resemble PHB granules were present in strains lacking a pair of genes essential for PHB synthesis and in wild-type cells under conditions that no PHB granules could be detected by fluorescence staining of PHB. Indeed, in these cells PHB could not be demonstrated chemically by GC/MS either. Based on the results gathered, it is concluded that not all the slightly electron-dense spherical inclusions are PHB granules in Synechocystis sp. PCC 6803. This result is potentially applicable to other cyanobacteria. Alternate assignments for these inclusions are discussed.

  9. Effect of Ni and Urea on Growth, Nitrate and Nutrients Concentration in Lettuce (Lactuca sativa Grown in Hydroponics

    Directory of Open Access Journals (Sweden)

    Hosein Nazari Mamaqani

    2017-02-01

    Full Text Available Introduction: The N source used in commercial hydroponic culture of vegetables is mainly NO3-N. The rate of NO3- uptake is usually high, particularly in leafy vegetables and it can be markedly increased when the NO3- supply in the environment is high. An abundant N supply leads to a high NO3-N absorption and accumulation in plants. When NO3- rich vegetables are consumed, various harmful effects on human health may occur such as met-hemoglobinemia (Blue Baby Syndrome and cancer. Keeping levels of NO3- below limits of FAO seems to be impossible without changing conventional fertilizer application techniques. The suitability of urea for the cultivation of field crops has been well documented. Urea is used as the main source of N fertilizer for crops grown in soil. Its use as N source for crops grown under the hydroponic system has yet to be evaluated. To hydrolyze urea, the enzyme urease requires Ni as a component. Substitution of urea for commonly used N03-N fertilizers in hydroponic culture of vegetables would not only enable to avoid excessive accumulation of N03- in plants but would also reduce the cost of production. Leafy vegetable crops, such as lettuce and spinach, contain large amounts of N03-N. Therefore, it is important to reduce N03- concentrations in hydroponically grown with lowest negative effects on yield. Materials and Methods: The experiments were carried outin greenhouse hydroponicsResearchFaculty of Agriculture, University of Tabriz in randomized complete block designwithtwo factors ureaatfivelevels of 0,25, 50, 75and100milligrams perliter(U0, U25,U50, U75, U100andnickelattwo levels of0and2mg per liter (Ni0, Ni2ofnickelsulfate(NiSO4in4replicatesusinglettuce(Lactuca sativa cv. Siyahoo. Plants fed with the modifiedHoagland solutionorhalf theconcentration. Treatments added to nutrient solution when plants were in four leaf stage. Plants were harvested 50 days after treatment. Different organs (leaves, stems and roots were separated

  10. An Sp1/Sp3 binding polymorphism confers methylation protection.

    Directory of Open Access Journals (Sweden)

    Yanis A Boumber

    2008-08-01

    Full Text Available Hundreds of genes show aberrant DNA hypermethylation in cancer, yet little is known about the causes of this hypermethylation. We identified RIL as a frequent methylation target in cancer. In search for factors that influence RIL hypermethylation, we found a 12-bp polymorphic sequence around its transcription start site that creates a long allele. Pyrosequencing of homozygous tumors revealed a 2.1-fold higher methylation for the short alleles (P<0.001. Bisulfite sequencing of cancers heterozygous for RIL showed that the short alleles are 3.1-fold more methylated than the long (P<0.001. The comparison of expression levels between unmethylated long and short EBV-transformed cell lines showed no difference in expression in vivo. Electrophorectic mobility shift assay showed that the inserted region of the long allele binds Sp1 and Sp3 transcription factors, a binding that is absent in the short allele. Transient transfection of RIL allele-specific transgenes showed no effects of the additional Sp1 site on transcription early on. However, stable transfection of methylation-seeded constructs showed gradually decreasing transcription levels from the short allele with eventual spreading of de novo methylation. In contrast, the long allele showed stable levels of expression over time as measured by luciferase and approximately 2-3-fold lower levels of methylation by bisulfite sequencing (P<0.001, suggesting that the polymorphic Sp1 site protects against time-dependent silencing. Our finding demonstrates that, in some genes, hypermethylation in cancer is dictated by protein-DNA interactions at the promoters and provides a novel mechanism by which genetic polymorphisms can influence an epigenetic state.

  11. Antioxidant capacity, polyphenol content and iron bioavailability from algae (Ulva sp., Sargassum sp. and Porphyra sp.) in human subjects.

    Science.gov (United States)

    García-Casal, Maria N; Ramírez, José; Leets, Irene; Pereira, Ana C; Quiroga, Maria F

    2009-01-01

    Marine algae are easily produced and are good sources of Fe. If this Fe is bioavailable, algae consumption could help to combat Fe deficiency and anaemia worldwide. The objective of the present study was to evaluate Fe bioavailability, polyphenol content and antioxidant capacity from three species of marine algae distributed worldwide. A total of eighty-three subjects received maize- or wheat-based meals containing marine algae (Ulva sp., Sargassum sp. and Porphyra sp.) in different proportions (2.5, 5.0 and 7.5 g) added to the water to prepare the dough. All meals administered contained radioactive Fe. Absorption was evaluated calculating radioactive Fe incorporation in subjects' blood. The three species of marine algae were analysed for polyphenol content and reducing power. Algae significantly increased Fe absorption in maize- or wheat-based meals, especially Sargassum sp., due to its high Fe content. Increases in absorption were dose-dependent and higher in wheat- than in maize-based meals. Total polyphenol content was 10.84, 18.43 and 80.39 gallic acid equivalents/g for Ulva sp., Porphyra sp. and Sargassum sp., respectively. The antioxidant capacity was also significantly higher in Sargassum sp. compared with the other two species analysed. Ulva sp., Sargassum sp. and Porphyra sp. are good sources of bioavailable Fe. Sargassum sp. resulted in the highest Fe intake due to its high Fe content, and a bread containing 7.5 g Sargassum sp. covers daily Fe needs. The high polyphenol content found in Sargassum sp. could be partly responsible for the antioxidant power reported here, and apparently did not affect Fe absorption.

  12. Growing different Lactuca genotypes aeroponically within a tropical greenhouse – Cool rootzone temperatures decreased rootzone ethylene concentrations and increased shoot growth

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    Tsui Wei CHOONG

    2016-09-01

    Full Text Available Temperate crops cannot grow well in the tropics without rootzone cooling. As cooling increased production costs, this experiment aimed to study the growth of various Lactuca genotypes and propose possible ways of reducing these costs, without compromising productivity. A recombinant inbred line (RIL of lettuce and its parental lines (L. serriola and L. sativa ‘Salinas’ were grown aeroponically in a tropical greenhouse under 24 C cool (C or warm fluctuating 30-36 C ambient (A rootzone temperature (RZT. Their roots were misted with Netherlands standard nutrient solution for 1 min, at intervals of either 5 min (A5, C5 or 10 min (A10, C10 in attempting to reduce electricity consumption and production costs. Lower mortality and higher productivity were observed in all genotypes when grown in C-RZT. Higher shoot fresh weight was observed under C5 than C10, for the RIL and L. serriola. Since ‘Salinas’ had similar shoot fresh weight at both C-RZ treatments, this may indicate it is more sensitive to RZT than water availability. Under A-RZ treatments, higher carotenoid content, with correspondingly higher nonphotochemical quenching, was observed in A10 for the RIL and ‘Salinas’. Further, total chlorophyll content was also highest at this RZ treatment for the RIL though photochemical quenching was contrastingly the lowest. Cumulatively, productivity was compromised at A10 as the RIL seemed to prioritize photoprotection over efficiency in photosynthesis, under conditions of higher RZT and lower water availability. Generally, higher RZ ethylene concentrations accumulated in A10 and C10 than A5 and C5, respectively – probably due to spray frequency exerting a greater effect on RZ ethylene accumulation than RZT. In the C5 RZ treatment, lowest RZ ethylene concentration corresponded with highest shoot fresh weight. As such, further research on ethylene (insensitivity and water use efficiency could be conducted to identify Lactuca cultivars

  13. Ulva lactuca polysaccharides prevent Wistar rat breast carcinogenesis through the augmentation of apoptosis, enhancement of antioxidant defense system, and suppression of inflammation

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    Abd-Ellatef GF

    2017-02-01

    Full Text Available Gamal-Eldein F Abd-Ellatef,1 Osama M Ahmed,2 Eman S Abdel-Reheim,2 Abdel-Hamid Z Abdel-Hamid,1 1Pharmaceutical and Drug Industries Research Division, Therapeutic Chemistry Department, National Research Centre, Cairo, Egypt; 2Division of Physiology, Department of Zoology, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt Background: Recently, several research studies have been focused on the isolation and function of the polysaccharides derived from different algal species, which revealed multiple biological activities such as antioxidant and antitumor activities. This study assesses the possible breast cancer chemopreventive properties of common seaweeds, sea lettuce, Ulva lactuca (ulvan polysaccharides using in vitro bioassays on human breast cancer cell line (MCF-7 and an in vivo animal model of breast carcinogenesis. Methods: Cytotoxic effect of ulvan polysaccharides on MCF-7 was tested in vitro. For an in vivo investigation, a single dose of 25 mg/kg body weight 7,12-dimethylbenz[a]anthracene (DMBA and ulvan polysaccharides (50 mg/kg body weight every other day for 10 weeks were administered orally to the Wistar rats. Results: Deleterious histopathological alterations in breast tissues including papillary cyst adenoma and hyperplasia of ductal epithelial lining with intraluminal necrotic materials and calcifications were observed in the DMBA-administered group. These lesions were prevented in the DMBA-administered group treated with ulvan polysaccharides. The immunohistochemical sections depicted that the treatment of DMBA-administered rats with ulvan polysaccharides markedly increased the lowered pro-apoptotic protein, p53, and decreased the elevated anti-apoptotic marker, bcl2, expression in the breast tissue. The elevated lipid peroxidation and the suppressed antioxidant enzyme activities in DMBA-administered control were significantly prevented by the treatment with ulvan polysaccharides. The elevated levels of inflammatory

  14. A surface complexation model of YREE sorption on Ulva lactuca in 0.05-5.0 M NaCl solutions

    Science.gov (United States)

    Zoll, Alison M.; Schijf, Johan

    2012-11-01

    We present distribution coefficients, log iKS, for the sorption of yttrium and the rare earth elements (YREEs) on BCR-279, a dehydrated tissue homogenate of a marine macroalga, Ulva lactuca, resembling materials featured in chemical engineering studies aimed at designing renewable biosorbents. Sorption experiments were conducted in NaCl solutions of different ionic strength (0.05, 0.5, and 5.0 M) at T = 25 °C over the pH range 2.7-8.5. Distribution coefficients based on separation of the dissolved and particulate phase by conventional filtration (3 kDa) using an existing pH-dependent model. Colloid-corrected values were renormalized to free-cation concentrations by accounting for YREE hydrolysis and chloride complexation. At each ionic strength, the pH dependence of the renormalized values is accurately described with a non-electrostatic surface complexation model (SCM) that incorporates YREE binding to three monoprotic functional groups, previously characterized by alkalimetric titration, as well as binding of YREE-hydroxide complexes (MOH2+) to the least acidic one (pKa ∼ 9.5). In non-linear regressions of the distribution coefficients as a function of pH, each pKa was fixed at its reported value, while stability constants of the four YREE surface complexes were used as adjustable parameters. Data for a single fresh U. lactuca specimen in 0.5 M NaCl show generally the same pH-dependent behavior but a lower degree of sorption and were excluded from the regressions. Good linear free-energy relations (LFERs) between stability constants of the YREE-acetate and YREE-hydroxide solution complex and surface complexes with the first and third functional group, respectively, support their prior tentative identifications as carboxyl and phenol. A similar confirmation for the second group is precluded by insufficient knowledge of the stability of YREE-phosphate complexes and a perceived lack of YREE binding in 0.05 M NaCl; this issue awaits further study. The results

  15. Seaweed extracts and unsaturated fatty acid constituents from the green alga Ulva lactuca as activators of the cytoprotective Nrf2–ARE pathway

    Science.gov (United States)

    Wang, Rui; Paul, Valerie J.; Luesch, Hendrik

    2013-01-01

    Increased amounts of reactive oxygen species (ROS) have been implicated in many pathological conditions, including cancer. The major machinery that the cell employs to neutralize excess ROS is through the activation of the antioxidant-response element (ARE) that controls the activation of many phase II detoxification enzymes. The transcription factor that recognizes the ARE, Nrf2, can be activated by a variety of small molecules, most of which contain an α,β-unsaturated carbonyl system. In the pursuit of chemopreventive agents from marine organisms, we built, fractionated, and screened a library of 30 field-collected eukaryotic algae from Florida. An edible green alga, Ulva lactuca, yielded multiple active fractions by ARE–luciferase reporter assay. We isolated three monounsaturated fatty acid (MUFA) derivatives as active components, including a new keto-type C18 fatty acid (1), the corresponding shorter chain C16 acid (2), and an amide derivative (3) of the C18 acid. Their chemical structures were elucidated by NMR and mass spectrometry. All three contain the conjugated enone motif between C7 and C9, which is thought to be responsible for the ARE activity. Subsequent biological studies focused on 1, the most active and abundant ARE activator isolated. C18 acid 1 induced the expression of ARE-regulated cytoprotective genes, including NAD(P)H:quinone oxidoreductase 1, heme oxygenase 1, thioredoxin reductase 1, both subunits of the glutamate–cysteine ligase (catalytic subunit and modifier subunit), and the cystine/glutamate exchange transporter, in IMR-32 human neuroblastoma cells. Its cellular activity requires the presence of Nrf2 and PI3K function, based on RNA interference and pharmacological inhibitor studies, respectively. Treatment with 1 led only to Nrf2 activation, and not the increase in production of NRF2 mRNA. To test its ARE activity and cytoprotective potential in vivo, we treated mice with a single dose of a U. lactuca fraction that was enriched

  16. Folhas de alface lisa (Lactuca sativa) minimamente processadas armazenadas em atmosfera modificada: análises físicas, químicas e físico-químicas Minimally processed smooth lettuce leaves (Lactuca sativa) stored at modified atmosphere: physica, chemical and physico-chemical analysis

    OpenAIRE

    Ellen M S Menezes; Érica C. Fernandes; Armando U. O. Sabaa-Srur

    2005-01-01

    Alfaces (Lactuca sativa) cv. lisa, após seleção e pré-lavagem, foram lavadas com água clorada a 5ºC contendo 150ppm de cloro residual livre e pH ajustado para 6.0, enxagüadas e centrifugadas por 8 minutos a 2200rpm. Em seguida, foram acondicionadas em embalagens plásticas de nylon poli 5 camadas, sem e com atmosfera modificada (N2 contendo 20ppm de O2 e no máximo 20ppm umidade) e estocadas a 4ºC. Durante 5 dias foram realizadas mensurações de pH, concentração de sólidos solúveis (graus Brix) ...

  17. Description and phylogenetic relationships of Spumochlamys perforata n. sp. and Spumochlamys bryora n. sp. (Amoebozoa, Arcellinida).

    Science.gov (United States)

    Kudryavtsev, Alexander; Pawlowski, Jan; Hausmann, Klaus

    2009-01-01

    Spumochlamys perforata n. sp. and Spumochlamys bryora n. sp. were isolated and described from dry epiphytic moss. The morphology and ultrastructure of both species clearly demonstrate that they belong to the genus Spumochlamys (family Microchlamyiidae). They differ from its only described member, Spumochlamys iliensis (as well as from species of Microchlamys), in the relief of the dorsal surface of the test, revealed by scanning electron microscopy, which can represent a good characteristic for species identification. They also differ in the structure of the dorsal part of the test wall (especially S. perforata). Small subunit ribosomal DNA-based molecular phylogenetic analyses show that Spumochlamys is a deeply branching lineage of the Arcellinida, without any close affinities. Actin gene sequence analysis places this genus within the Tubulinea, close to two other arcellinid lineages but without forming a monophyletic group with them. These data together strongly suggest that the lack of resolution in the arcellinid molecular phylogenies is due to serious undersampling of taxa, a limited number of sequence data, and high divergence rates in most of the species.

  18. Supplemental upward lighting from underneath to obtain higher marketable lettuce (Lactuca sativa leaf fresh weight by retarding senescence of outer leaves

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    Geng eZhang

    2015-12-01

    Full Text Available Recently, the so-called plant factory with artificial lighting (PFAL approach has been developed to provide safe and steady food production. Although PFALs can produce high-yielding and high-quality plants, the high plant density in these systems accelerates leaf senescence in the bottom (or outer leaves owing to shading by the upper (or inner leaves and by neighboring plants. This decreases yield and increases labor costs for trimming. Thus, the establishment of cultivation methods to retard senescence of outer leaves is an important research goal to improve PFAL yield and profitability. In the present study, we developed an LED lighting apparatus that would optimize light conditions for PFAL cultivation of a leafy vegetable. Lettuce (Lactuca sativa L. was hydroponically grown under white, red, or blue LEDs, with light provided from above (downward, with or without supplemental upward lighting from underneath the plant. White LEDs proved more appropriate for lettuce growth than red or blue LEDs, and the supplemental lighting retarded the senescence of outer leaves and decreased waste (i.e., dead or low-quality senescent leaves, leading to an improvement of the marketable leaf fresh weight.

  19. Standardized extract of Lactuca sativa Linn. and its fractions abrogates scopolamine-induced amnesia in mice: A possible cholinergic and antioxidant mechanism.

    Science.gov (United States)

    Malik, Jai; Kaur, Jagpreet; Choudhary, Sunayna

    2017-02-28

    The present study was designed to evaluate the efficacy of Lactuca sativa (LS) Linn. (Asteraceae) against scopolamine- induced amnesia and to validate its traditional claim as memory enhancer. Ethanol extract of fresh LS leaves (LSEE), standardized on the basis of quercetin content, was successively partitioned using various solvents viz., hexane, ethyl acetate, and n-butanol in increasing order of polarity. LSEE (50, 100, and 200 mg/kg) and its various fractions (at a dose equivalent to dose of LSEE exhibiting maximum activity), administered orally for 14 days, were evaluated for their memory enhancing effect against scopolamine-induced (1 mg/kg, i.p.) amnesia in 3-4 months old male Laca mice (n = 6 in each group). The memory enhancing effect was evaluated using behavioural (elevated plus maze, novel object recognition and Morris water maze tests) and biochemical parameters (acetylcholinesterase activity, malonaldehyde, superoxide dismutase, nitrite, catalase, and reduced gultathione content). The results of the test substances were compared with both scopolamine and donepezil that was used as a standard memory enhancer and acetylcholinesterase inhibitor. Scopolamine elicit marked deterioration of memory and alteration in biochemical parameters in comparison to the control group. LSEE and its n-butanol and aqueous fractions significantly (P memory impairment through its acetylcholinesterase inhibitory and antioxidant activity validating its traditional claim.

  20. Increased exposure to UV-B radiation during early development leads to enhanced photoprotection and improved long-term performance in Lactuca sativa.

    Science.gov (United States)

    Wargent, Jason J; Elfadly, Eslam M; Moore, Jason P; Paul, Nigel D

    2011-08-01

    Plant responses to solar UV radiation are numerous and have often been considered from a perspective of negative outcomes for plant productivity. In this study, we used two experimental approaches consisting of: (1) field-based spectrally modifying filters in addition to (2) controlled indoor exposure to UV-B, to examine the effects of UV radiation on growth and photosynthetic performance of lettuce (Lactuca sativa L.) seedlings. Various aspects of growth were affected in plants grown under a UV-inclusive environment compared to a UV-depleted environment, including reductions in leaf expansion, increases in leaf thickness and the rate of net photosynthesis. After transplantation to a uniform field environment, lettuce plants initially propagated under the UV-inclusive environment exhibited higher harvestable yields than those from a UV-depleted environment. In controlled conditions, photosynthetic rates were higher in plants grown in the presence of UV-B radiation, and relative growth of plants pre-acclimatized to UV-B was also increased, in addition to higher maximum photochemical efficiency of photosystem II (PSII) (F(v) /F(m) ) following subsequent exposure to high photosynthetically active radiation (PAR) and temperature stress. Our findings are discussed within the context of sustainability in agriculture and the paradigm shift in photobiology which such beneficial responses to UV radiation could represent. © 2011 Blackwell Publishing Ltd.

  1. Assembly of the Lactuca sativa, L. cv. Tizian draft genome sequence reveals differences within major resistance complex 1 as compared to the cv. Salinas reference genome.

    Science.gov (United States)

    Verwaaijen, Bart; Wibberg, Daniel; Nelkner, Johanna; Gordin, Miriam; Rupp, Oliver; Winkler, Anika; Bremges, Andreas; Blom, Jochen; Grosch, Rita; Pühler, Alfred; Schlüter, Andreas

    2018-02-10

    Lettuce (Lactuca sativa, L.) is an important annual plant of the family Asteraceae (Compositae). The commercial lettuce cultivar Tizian has been used in various scientific studies investigating the interaction of the plant with phytopathogens or biological control agents. Here, we present the de novo draft genome sequencing and gene prediction for this specific cultivar derived from transcriptome sequence data. The assembled scaffolds amount to a size of 2.22 Gb. Based on RNAseq data, 31,112 transcript isoforms were identified. Functional predictions for these transcripts were determined within the GenDBE annotation platform. Comparison with the cv. Salinas reference genome revealed a high degree of sequence similarity on genome and transcriptome levels, with an average amino acid identity of 99%. Furthermore, it was observed that two large regions are either missing or are highly divergent within the cv. Tizian genome compared to cv. Salinas. One of these regions covers the major resistance complex 1 region of cv. Salinas. The cv. Tizian draft genome sequence provides a valuable resource for future functional and transcriptome analyses focused on this lettuce cultivar. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Lettuce Production Hydroponics (Lactuca Sativa L. for the Promotion of Self-Management in Basic School Bolivariana “Los Naranjos”

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    Luis Alfredo Díaz

    2017-05-01

    Full Text Available The present research aims at the promotion of the Hydroponic Lettuce Cultivation (Lactuca Sativa L. as a self - management alternative in the Bolivarian Basic School “Los Naranjos”, Calderas parish, Bolívar municipality of Barinas state. The nature of the study is framed under the modality of the qualitative paradigm, adopting the method of Participatory Action Research. On the other hand, the research will be conducted in (4 four phases: Phase I. Diagnosis, Phase II. Elaboration of the action plan, Phase III. Implementation of the action plan, Phase IV. Reflection, interpretation and integration of results. Information triangulation was used to analyze the information in order to cross-check information from key informants. For all of the above, this study constitutes a significant contribution to the teaching and learning process as it is the responsibility of the family and teachers as promoters and agents of dissemination of knowledge, accept the responsibility in this process of placing children in contact And girls with new techniques of cultivation, in this case with the hydroponic technique, since its early years, so that this is a pleasurable, pleasant and encouraging experience that accompanies him for the rest of his life.

  3. Residual compost from the production of Bactris gasipaes Kunth and Pleurotus ostreatus as soil conditioners for Lactuca sativa ‘Veronica’

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    Marcelo Barba Bellettini

    2017-05-01

    Full Text Available This study evaluated the residual compost from the production of Bactris gasipaes Kunth (pupunha heart of palm (RP and the mushroom Pleurotus ostreatus (RM. The residuals were used as soil conditioners for Lactuca sativa ‘Veronica’ crops. After adding RP and RM to the soil, all treatments exhibited similar behaviors and soils in each treatment were classified as eutrophic. Soil treatments involving increased application of residual compost resulted in the production of lettuce with greater widths because of an increase in the angle between the stem and leaf, resulting from a lack of nitrogen available to the plant. Soil treatments with 5% of RP and RM resulted in a 1.7 and 1.2 times (44% and 22%, respectively decrease in dry weight of lettuce, as compared to the soil without residual compost addition. The addition of RP and RM as soil substrate reduced the growth of lettuce compared to the soil without residual compost. In general, the possibility of replacing chemical fertilizers (NPK with RP or RM without previous composting was found to be inefficient. The resultant dry weight parameters were below the commercial level, and a complete period of composting RP and RM was deemed necessary for incorporating nitrogen into the soil. Lignocellulosic mushrooms such as Pleurotus spp. present highly fibrous residual compost with low nitrogen content, thus requiring a full period of composting before subsequent use in soil enrichment for various crops.

  4. Acclimation to UV-B radiation and visible light in Lactuca sativa involves up-regulation of photosynthetic performance and orchestration of metabolome-wide responses.

    Science.gov (United States)

    Wargent, J J; Nelson, B C W; McGhie, T K; Barnes, P W

    2015-05-01

    UV-B radiation is often viewed as a source of stress for higher plants. In particular, photosynthetic function has been described as a common target for UV-B impairment; yet as our understanding of UV-B photomorphogenesis increases, there are opportunities to expand the emerging paradigm of regulatory UV response. Lactuca sativa is an important dietary crop species and is often subjected to rapid sunlight exposure at field transfer. Acclimation to UV-B and visible light conditions in L. sativa was dissected using gas exchange and chlorophyll fluorescence measurements, in addition to non-destructive assessments of UV epidermal shielding (SUV ). After UV-B treatment, seedlings were subjected to wide-range metabolomic analysis using liquid chromatography hybrid quadrupole time-of-flight high-resolution mass spectrometry (LC-QTOF-HRMS). During the acclimation period, net photosynthetic rate increased in UV-treated plants, epidermal UV shielding increased in both subsets of plants transferred to the acclimatory conditions (UV+/UV- plants) and Fv /Fm declined slightly in UV+/UV- plants. Metabolomic analysis revealed that a key group of secondary compounds was up-regulated by higher light conditions, yet several of these compounds were elevated further by UV-B radiation. In conclusion, acclimation to UV-B radiation involves co-protection from the effects of visible light, and responses to UV-B radiation at a photosynthetic level may not be consistently viewed as damaging to plant development. © 2014 John Wiley & Sons Ltd.

  5. [Combination of phosphorus solubilizing and mobilizing fungi with phosphate rocks and volcanic materials to promote plant growth of lettuce (Lactuca sativa L.)].

    Science.gov (United States)

    Velázquez, María S; Cabello, Marta N; Elíades, Lorena A; Russo, María L; Allegrucci, Natalia; Schalamuk, Santiago

    Arbuscular mycorrhizal fungi (AMF) increase the uptake of soluble phosphates, while phosphorus solubilizing fungi (S) promote solubilization of insoluble phosphates complexes, favoring plant nutrition. Another alternative to maintaining crop productivity is to combine minerals and rocks that provide nutrients and other desirable properties. The aim of this work was to combine AMF and S with pyroclastic materials (ashes and pumices) from Puyehue volcano and phosphate rocks (PR) from Rio Chico Group (Chubut) - to formulate a substrate for the production of potted Lactuca sativa. A mixture of Terrafertil®:ashes was used as substrate. Penicillium thomii was the solubilizing fungus and Rhizophagus intraradices spores (AMF) was the P mobilizer (AEGIS® Irriga). The treatments were: 1) Substrate; 2) Substrate+AMF; 3) Substrate+S; 4) Substrate+AMF+S; 5) Substrate: PR; 6) Substrate: PR+AMF; 7) Substrate: PR+S and 8) Substrate: PR+AMF+S. Three replicates were performed per treatment. All parameters evaluated (total and assimilable P content in substrate, P in plant tissue and plant dry biomass) were significantly higher in plants grown in substrate containing PR and inoculas with S and AMF. This work confirms that the combination of S/AMF with Puyehue volcanic ashes, PR from the Río Chico Group and a commercial substrate promote the growth of L. sativa, thus increasing the added value of national geomaterials. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  6. MECANISMOS DE AÇÃO DO EXTRATO AQUOSO DE Piper amalago EM CÉLULAS MERISTEMÁTICAS DE Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Thammyres de Assis Alves

    2017-01-01

    Full Text Available Para manutenção da segurança alimentar o uso de agrotóxicos tem aumentado em todo o mundo, sendo o Brasil o seu maior consumidor desde 2009. Porém, os danos ambientais e à saúde humana, causados por essas substâncias sintéticas, tem provocado preocupações. Uma forma de amenizar o uso dos agrotóxicos é substituí-los totalmente ou em partes por compostos naturais, encontrados em plantas. Piper amalago é uma espécie que possui diferentes compostos químicos em sua constituição, tais como: alcaloides, amidos, terpenos e esteroides, o que determina nas suas diferentes atividades biológicas. Em virtude da sua constituição química, essa espécie é indicada para estudos de alelopatia. Assim, o presente trabalho objetivou avaliar o potencial mutagênico do extrato aquoso de P.  amalago através de bioensaio em Lactuca sativa. Para isso, análises de fitotoxicidade e citotoxicidade foram realizadas. Os dados obtidos foram submetidos ao teste de Dunnett com 5% de significância. Os resultados demonstram o potencial mutagênico do extrato aquoso de P. amalago em L. sativa, bem como, seus mecanismos de ação: clastogênicos e aneugênicos.

  7. Influence of fine process particles enriched with metals and metalloids on Lactuca sativa L. leaf fatty acid composition following air and/or soil-plant field exposure

    International Nuclear Information System (INIS)

    Schreck, Eva; Laplanche, Christophe; Le Guédard, Marina; Bessoule, Jean-Jacques; Austruy, Annabelle; Xiong, Tiantian; Foucault, Yann; Dumat, Camille

    2013-01-01

    We investigate the effect of both foliar and root uptake of a mixture of metal(loid)s on the fatty acid composition of plant leaves. Our objectives are to determine whether both contamination pathways have a similar effect and whether they interact. Lactuca sativa L. were exposed to fine process particles enriched with metal(loid)s in an industrial area. Data from a first experiment were used to conduct an exploratory statistical analysis which findings were successfully cross-validated by using the data from a second one. Both foliar and root pathways impact plant leaf fatty acid composition and do not interact. Z index (dimensionless quantity), weighted product of fatty acid concentration ratios was built up from the statistical analyses. It provides new insights on the mechanisms involved in metal uptake and phytotoxicity. Plant leaf fatty acid composition is a robust and fruitful approach to detect and understand the effects of metal(loid) contamination on plants. -- Highlights: •The study compares foliar and root transfers of metal(loid)s and their effects on plants. •Field experiments are performed combining ecotoxicological and statistical analyses. •The use of leaf fatty acid composition is a relevant indicator of exposure pathway. •The uptake pathways are independent, with an additive effect in terms of phytotoxicity. -- Metal uptake via both foliar and root pathways alters in a distinctive manner the fatty acid composition of lettuce leaves

  8. Effect of acute ingestion of fresh and stored lettuce (Lactuca sativa) on plasma total antioxidant capacity and antioxidant levels in human subjects.

    Science.gov (United States)

    Serafini, Mauro; Bugianesi, Rossana; Salucci, Monica; Azzini, Elena; Raguzzini, Anna; Maiani, Giuseppe

    2002-12-01

    The present study investigated whether storage under modified-atmosphere packaging (MAP) affected the antioxidant properties of fresh lettuce (Lactuca sativa). Eleven healthy volunteers (six men, five women) consumed 250 g fresh lettuce, and blood was sampled before (0 h) and 2, 3 and 6 h after consumption. The protocol was repeated 3 d later with the same lettuce stored at 5 degrees C under MAP conditions (O2-N2 (5:95, v/v)). Results showed that after ingestion of fresh lettuce, plasma total radical-trapping antioxidant potential (TRAP), measured as area under the curve, was significantly higher (1.3 (sem 0.3) mmol/l per 6 h; Plettuce (0.1 (sem 0.2) mmol/l per 6 h). Plasma TRAP, quercetin and p-coumaric acid were significantly different from baseline values (Plettuce ingestion. Caffeic acid increased significantly at 3 h (Plettuce for all the measured markers. Our present results showed that ingestion of MAP-stored lettuce does not modify plasma redox status in healthy subjects. Further research is needed to develop post-harvesting techniques able to preserve the bioactive molecule content of plant food.

  9. Phytotoxic effects of leukamenin E (an ent-kaurene diterpenoid) on root growth and root hair development in Lactuca sativa L. seedlings.

    Science.gov (United States)

    Ding, Lan; Qi, Linlin; Jing, Hongwei; Li, Juan; Wang, Wei; Wang, Tao

    2008-11-01

    Leukamenin E, an ent-kaurene diterpenoid isolated from Isodon racemosa (Hemsl) Hara, showed phytotoxic effects on root growth and root hair development of lettuce seedlings (Lactuca sativa L.). Lower concentrations (10 microM) of leukamenin E did not affect root growth, but at concentrations higher than 50 microM, the rate was inhibited. The influence of leukamenin E on root growth rate was closely correlated with alterations in the mitotic index. A low incidence of aberrant mitosis image was observed when lettuce roots were treated with higher concentrations (100 and 200 microM) of leukamenin E. This suggests that inhibition of root growth may be due to inhibition of cell division. All tested concentrations of the diterpenoid (10 microM or more) inhibited root hair development in a dose-dependent manner. At a concentration of 80 microM, leukamenin E completely blocked root hair initiation. Application of Ag(+)-an ethylene action inhibitor-to lettuce seedlings inhibited root hair elongation similar to the diterpenoid. Enhanced root hair length was stimulated by exogenous ethephon-an ethylene-releasing agent-and could be reversed by addition of leukamenin E. This suggests that leukamenin E may act as a potential ethylene action antagonist in the inhibition of lettuce root hair development. We conclude that leukamenin E may curb root hair development by interfering with ethylene action at concentrations above 10 microM and inhibits root growth via inhibition of cell division at concentrations above 50 microM.

  10. Light-induced root hair formation in lettuce (Lactuca sativa L. cv. Grand Rapids) roots at low pH is brought by chlorogenic acid synthesis and sugar.

    Science.gov (United States)

    Narukawa, Megumi; Watanabe, Keiji; Inoue, Yasunori

    2010-11-01

    Previously, we reported that chlorogenic acid (CGA) facilitated root hair formation at pH 4.0 in lettuce (Lactuca sativa L. cv. Grand Rapids). Light was essential for this process. In the present study, we determined relationships between CGA, light, and sugar during root hair formation in lettuce seedlings. The amount of CGA increased with white light in intact seedlings. Exogenously applied CGA restored root hair formation in dark-grown intact seedlings at pH 4.0. However, no root hair formation was induced in decapitated seedlings regardless of light exposure and CGA application. Application of sucrose or glucose induced both root hair formation and CGA synthesis in light-grown decapitated seedlings at pH 4.0. Blue light was the most effective for both root hair formation and CGA synthesis when supplied with sucrose to decapitated seedlings. Addition of sucrose and CGA together induced root hair formation at pH 4.0 in dark-grown decapitated seedlings. Results suggest that light induced CGA synthesis from sugar in the roots. Sugar was also required for root hair formation other than starting material of CGA synthesis. In addition, an unknown low pH-induced factor was essential for lettuce root hair formation.

  11. Regulation of cell division and growth in roots of Lactuca sativa L. seedlings by the Ent-Kaurene diterpenoid rabdosin B.

    Science.gov (United States)

    Ding, Lan; Jing, Hongwei; Qin, Bo; Qi, Linlin; Li, Jing; Wang, Tao; Liu, Guoan

    2010-05-01

    Rabdosin B, an ent-kaurene diterpenoid purified from the air-dried aerial parts of Isodon japonica (Burm.f) Hara var. galaucocalyx (maxin) Hara, showed a biphasic, dose-dependent effect on root growth and a strong inhibitory effect on root hair development in lettuce seedlings (Lactuca sativa L.). Lower concentrations of rabdosin B (20-80 microM) significantly promoted root growth, but its higher levels at 120-200 microM, by contrast, had inhibitory effects. Additionally, all tested concentrations (10-40 microM) inhibited root hair development of seedlings in a dose-dependent manner. Further investigations on the underlying mechanism revealed that the promotion effect of rabdosin B at the lower concentrations resulted from increasing the cell length in the mature region and enhancing the mitotic activity of meristematic cells in seedlings' root tips. In contrast, rabdosin B at higher concentrations inhibited root growth by affecting both cell length in the mature region and division of meristematic cells. Comet assay and cell cycle analysis demonstrated that the decrease of mitotic activity of root meristematic cells was due to DNA damage induced cell cycle retardation of the G(2) phase and S phase at different times.

  12. Humic substances can modulate the allelopathic potential of caffeic, ferulic, and salicylic acids for seedlings of lettuce (Lactuca sativa L.) and tomato (Lycopersicon esculentum Mill.).

    Science.gov (United States)

    Loffredo, Elisabetta; Monaci, Linda; Senesi, Nicola

    2005-11-30

    The capacity of a leonardite humic acid (LHA), a soil humic acid (SHA), and a soil fulvic acid (SFA) in modulating the allelopathic potential of caffeic acid (CA), ferulic acid (FA), and salicylic acid (SA) on seedlings of lettuce (Lactuca sativa L.) and tomato (Lycopersicon esculentum Mill.) was investigated. Lettuce showed a sensitivity greater than that of tomato to CA, FA, and SA phytotoxicity, which was significantly reduced or even suppressed in the presence of SHA or SFA, especially at the highest dose, but not LHA. In general, SFA was slightly more active than SHA, and the efficiency of the action depended on their concentration, the plant species and the organ examined, and the allelochemical. The daily measured residual concentration of CA and FA decreased drastically and that of SA slightly in the presence of germinating seeds of lettuce, which were thus able to absorb and/or enhance the degradation of CA and FA. The adsorption capacity of SHA for the three allelochemicals was small and decreased in the order FA > CA > SA, thus suggesting that adsorption could be a relevant mechanism, but not the only one, involved in the "antiallelopathic" action.

  13. Metabolomics of Ulva lactuca Linnaeus (Chlorophyta) exposed to oil fuels: Fourier transform infrared spectroscopy and multivariate analysis as tools for metabolic fingerprint.

    Science.gov (United States)

    Pilatti, Fernanda Kokowicz; Ramlov, Fernanda; Schmidt, Eder Carlos; Costa, Christopher; Oliveira, Eva Regina de; Bauer, Claudia M; Rocha, Miguel; Bouzon, Zenilda Laurita; Maraschin, Marcelo

    2017-01-30

    Fossil fuels, e.g. gasoline and diesel oil, account for substantial share of the pollution that affects marine ecosystems. Environmental metabolomics is an emerging field that may help unravel the effect of these xenobiotics on seaweeds and provide methodologies for biomonitoring coastal ecosystems. In the present study, FTIR and multivariate analysis were used to discriminate metabolic profiles of Ulva lactuca after in vitro exposure to diesel oil and gasoline, in combinations of concentrations (0.001%, 0.01%, 0.1%, and 1.0% - v/v) and times of exposure (30min, 1h, 12h, and 24h). PCA and HCA performed on entire mid-infrared spectral window were able to discriminate diesel oil-exposed thalli from the gasoline-exposed ones. HCA performed on spectral window related to the protein absorbance (1700-1500cm -1 ) enabled the best discrimination between gasoline-exposed samples regarding the time of exposure, and between diesel oil-exposed samples according to the concentration. The results indicate that the combination of FTIR with multivariate analysis is a simple and efficient methodology for metabolic profiling with potential use for biomonitoring strategies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Production characteristics of lettuce Lactuca sativa L. in the frame of the first crop tests in the Higher Plant Chamber integrated into the MELiSSA Pilot Plant

    Science.gov (United States)

    Tikhomirova, Natalia; Lawson, Jamie; Stasiak, Michael; Dixon, Mike; Paille, Christel; Peiro, Enrique; Fossen, Arnaud; Godia, Francesc

    Micro-Ecological Life Support System Alternative (MELiSSA) is an artificial closed ecosystem that is considered a tool for the development of a bioregenerative life support system for manned space missions. One of the five compartments of MELiSSA loop -Higher Plant Chamber was recently integrated into the MELiSSA Pilot Plant facility at Universitat Aut`noma deo Barcelona. The main contributions expected by integration of this photosynthetic compartment are oxygen, water, vegetable food production and CO2 consumption. Production characteristics of Lactuca sativa L., as a MELiSSA candidate crop, were investigated in this work in the first crop experiments in the MELiSSA Pilot Plant facility. The plants were grown in batch culture and totaled 100 plants with a growing area 5 m long and 1 m wide in a sealed controlled environment. Several replicates of the experiments were carried out with varying duration. It was shown that after 46 days of lettuce cultivation dry edible biomass averaged 27, 2 g per plant. However accumulation of oxygen in the chamber, which required purging of the chamber, and decrease in the food value of the plants was observed. Reducing the duration of the tests allowed uninterrupted test without opening the system and also allowed estimation of the crop's carbon balance. Results of productivity, tissue composition, nutrient uptake and canopy photosynthesis of lettuce regardless of test duration are discussed in the paper.

  15. The Impact of Biochar Application on Soil Properties and Plant Growth of Pot Grown Lettuce (Lactuca sativa and Cabbage (Brassica chinensis

    Directory of Open Access Journals (Sweden)

    Stephan Haefele

    2013-05-01

    Full Text Available The effect of rice-husk char (potentially biochar application on the growth of transplanted lettuce (Lactuca sativa and Chinese cabbage (Brassica chinensis was assessed in a pot experiment over a three crop (lettuce-cabbage-lettuce cycle in Cambodia. The biochar was the by-product of a rice-husk gasification unit and consisted of 28.7% carbon (C by mass. Biochar application rates to potting medium of 25, 50 and 150 g kg−1 were used with and without locally available fertilizers (a mixture of compost, liquid compost and lake sediment. The rice-husk biochar used was slightly alkaline (pH 7.79, increased the pH of the soil, and contained elevated levels of some trace metals and exchangeable cations (K, Ca and Mg in comparison to the soil. The biochar treatments were found to increase the final biomass, root biomass, plant height and number of leaves in all the cropping cycles in comparison to no biochar treatments. The greatest biomass increase due to biochar additions (903% was found in the soils without fertilization, rather than fertilized soils (483% with the same biochar application as in the “without fertilization” case. Over the cropping cycles the impact was reduced; a 363% increase in biomass was observed in the third lettuce cycle.

  16. Analysis of bacteria, parasites, and heavy metals in lettuce (Lactuca sativa) and rocket salad (Eruca sativa L.) irrigated with treated effluent from a biological wastewater treatment plant.

    Science.gov (United States)

    Nikaido, Meire; Tonani, Karina A A; Julião, Fabiana C; Trevilato, Tânia M B; Takayanagui, Angela M M; Sanches, Sérgio M; Domingo, José L; Segura-Muñoz, Susana I

    2010-06-01

    This study aimed to evaluate the viability of using treated residuary water from the Biological Wastewater Treatment Plant of Ribeirão Preto to grow vegetables, through the characterization and quantification of parasites, coliforms, and heavy metals. Three equal cultivation areas were prepared. The first was irrigated with treated/chlorinated (0.2 mg L(-1)) wastewater, the second one with treated wastewater without chlorination, and the third site with potable water, which was the control group. The presence of Hymenolepis nana, Enterobius vermicularis, nematode larvae, and Entamoeba coli was verified in lettuce (Lactuca sativa) samples. Although nematode larvae were observed in rocket salad (Eruca sativa L.), no significant differences were found between the number of parasites and type of irrigation water used. No significant differences were found between the number of fecal coliforms in vegetables and the different types of irrigation. However, the vegetables irrigated with treated effluent without chlorination showed higher levels of fecal coliforms. The risk of pathogens is reduced with bleach addition to the treated effluent at 0.2 mg/L. Concentration of heavy metals in vegetables does not mean significant risks to human health, according with the parameters recommended by the World Health Organization.

  17. Growth and phenolic compounds of Lactuca sativa L. grown in a closed-type plant production system with UV-A, -B, or -C lamp.

    Science.gov (United States)

    Lee, Min-Jeong; Son, Jung Eek; Oh, Myung-Min

    2014-01-30

    The production of high-quality crops based on phytochemicals is a strategy for accelerating the practical use of plant factories. Previous studies have demonstrated that ultraviolet (UV) light is effective in improving phytochemical production. This study aimed to determine the effect of various UV wavelengths on growth and phenolic compound accumulation in lettuce (Lactuca sativa L.) grown in a closed-type plant production system. Seven days, 1 day and 0.25 day were determined as the upper limit of the irradiation periods for UV-A, -B, and -C, respectively, in the lettuce based on physiological disorders and the fluorescence parameter F(v)/F(m). Continuous UV-A treatment significantly induced the accumulation of phenolic compounds and antioxidants until 4 days of treatment without growth inhibition, consistent with an increase in phenylalanine ammonia lyase (PAL) gene expression and PAL activity. Repeated or gradual UV-B exposure yielded approximately 1.4-3.6 times more total phenolics and antioxidants, respectively, than the controls did 2 days after the treatments, although both treatments inhibited lettuce growth. Repeated UV-C exposure increased phenolics but severely inhibited the growth of lettuce plants. Our data suggest that UV irradiation can improve the accumulation of phenolic compounds with antioxidant properties in lettuce cultivated in plant factories. © 2013 Society of Chemical Industry.

  18. Investigating the ability of Pseudomonas fluorescens UW4 to reduce cadmium stress in Lactuca sativa via an intervention in the ethylene biosynthetic pathway.

    Science.gov (United States)

    Albano, Lucas J; Macfie, Sheila M

    2016-12-01

    A typical plant response to any biotic or abiotic stress, including cadmium (Cd), involves increased ethylene synthesis, which causes senescence of the affected plant part. Stressed plants can experience reduced ethylene and improved growth if they are inoculated with bacteria that have the enzyme ACC deaminase, which metabolizes the ethylene precursor ACC (1-aminocyclopropane-1-carboxylate). We investigated whether one such bacterium, Pseudomonas fluorescens UW4, reduces the production of ethylene and improves the growth of lettuce (Lactuca sativa) sown in Cd-contaminated potting material (PRO-MIX® BX). Plants were inoculated with the wild-type P. fluorescens UW4 or a mutant strain that cannot produce ACC deaminase. Cadmium-treated plants contained up to 50 times more Cd than did control plants. In noninoculated plants, Cd induced a 5-fold increase in ethylene concentration. The wild-type bacterium prevented Cd-induced reductions in root biomass but there was no relationship between Cd treatment and ethylene production in inoculated plants. In contrast, when the concentration of ethylene was plotted against the extent of bacterial colonization of the roots, increased colonization with wild-type P. fluorescens UW4 was associated with 20% less ethylene production. Ours is the first study to show that the protective effect of this bacterium is proportional to the quantity of bacteria on the root surface.

  19. Evaluation of anti-inflammatory activity and fast UHPLC-DAD-IT-TOF profiling of polyphenolic compounds extracted from green lettuce (Lactuca sativa L.; var. Maravilla de Verano).

    Science.gov (United States)

    Pepe, Giacomo; Sommella, Eduardo; Manfra, Michele; De Nisco, Mauro; Tenore, Gian Carlo; Scopa, Antonio; Sofo, Adriano; Marzocco, Stefania; Adesso, Simona; Novellino, Tiziana; Campiglia, Pietro

    2015-01-15

    Fresh cut vegetables represent a widely consumed food worldwide. Among these, lettuce (Lactuca sativa L.) is one of the most popular on the market. The growing interest for this "healthy" food is related to the content of bioactive compounds, especially polyphenols, that show many beneficial effects. In this study, we report the anti-inflammatory and antioxidant potential of polyphenols extracted from lettuce (var. Maravilla de Verano), in J774A.1 macrophages stimulated with Escherichia coli lipopolysaccharide (LPS). Lettuce extract significantly decreased reactive oxygen species, nitric oxide release, inducible nitric oxide synthase and cycloxygenase-2 expression. A detailed quali/quantitative profiling of the polyphenolic content was carried out, obtaining fast separation (10 min), good retention time and peak area repeatability, (RSD% 0.80 and 8.68, respectively) as well as linearity (R(2)⩾ 0.999) and mass accuracy (⩽ 5 ppm). Our results show the importance in the diet of this cheap and popular food for his healthy properties. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Linking the morphological and metabolomic response of Lactuca sativa L exposed to emerging contaminants using GC × GC-MS and chemometric tools.

    Science.gov (United States)

    Hurtado, Carlos; Parastar, Hadi; Matamoros, Víctor; Piña, Benjamín; Tauler, Romà; Bayona, Josep M

    2017-07-26

    The occurrence of contaminants of emerging concern (CECs) in irrigation waters (up to low μg L -1 ) and irrigated crops (ng g -1 in dry weight) has been reported, but the linkage between plant morphological changes and plant metabolomic response has not yet been addressed. In this study, a non-targeted metabolomic analysis was performed on lettuce (Lactuca sativa L) exposed to 11 CECs (pharmaceuticals, personal care products, anticorrosive agents and surfactants) by irrigation. The plants were watered with different CEC concentrations (0-50 µg L -1 ) for 34 days under controlled conditions and then harvested, extracted, derivatised and analysed by comprehensive two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer (GC × GC-TOFMS). The resulting raw data were analysed using multivariate curve resolution (MCR) and partial least squares (PLS) methods. The metabolic response indicates that exposure to CECs at environmentally relevant concentrations (0.05 µg L -1 ) can cause significant metabolic alterations in plants (carbohydrate metabolism, the citric acid cycle, pentose phosphate pathway and glutathione pathway) linked to changes in morphological parameters (leaf height, stem width) and chlorophyll content.

  1. Particle trajectories in seeds of Lactuca sativa and chromosome aberrations after exposure to cosmic heavy ions on cosmos biosatellites 8 and 9

    Science.gov (United States)

    Facius, R.; Scherer, K.; Reitz, G.; Bücker, H.; Nevzgodina, L. V.; Maximova, E. N.

    1994-10-01

    The potentially specific importance of the heavy ions of the galactic cosmic radiation for radiation protection in manned spaceflight continues to stimulate in situ, i.e., spaceflight experiments to investigate their radiobiological properties. Chromosome aberrations as an expression of a direct assault on the genome are of particular interest in view of cancerogenesis being the primary radiation risk for man in space. In such investigations the establishment of the geometrical correlation between heavy ions' trajectories and the location of radiation sensitive biological substructures is an essential task. The overall qualitative and quantitative precision achieved for the identification of particle trajectories in the order of 2~10 μm as well as the contributing sources of uncertainties are discussed. We describe how this was achieved for seeds of Lactuca sativa as biological test organisms, whose location and orientation had to be derived from contact photographies displaying their outlines and those of the holder plates only. The incidence of chromosome aberrations in cells exposed during the COSMOS 1887 (Biosatellite 8) and the COSMOS 2044 (Biosatellite 9) mission was determined for seeds hit by cosmic heavy ions. In those seeds the incidence of both single and multiple chromosome aberrations was enhanced. The results of the Biosatellite 9 experiment, however, are confounded by spaceflight effects unrelated to the passage of heavy ions.

  2. Effect of SPL (Spent Pot Liner) and its main components on root growth, mitotic activity and phosphorylation of Histone H3 in Lactuca sativa L.

    Science.gov (United States)

    Freitas, Aline Silva; Fontes Cunha, Isabela Martinez; Andrade-Vieira, Larissa Fonseca; Techio, Vânia Helena

    2016-02-01

    Spent Pot Liner (SPL) is a solid waste from the aluminum industry frequently disposed of in industrial landfills; it can be leached and contaminate the soil, sources of drinking water and plantations, and thus may pose a risk to human health and to ecosystems. Its composition is high variable, including cyanide, fluoride and aluminum salts, which are highly toxic and environmental pollutants. This study evaluated the effect of SPL and its main components on root growth and the mitosis of Lactuca sativa, by investigating the mechanisms of cellular and chromosomal alterations with the aid of immunolocalization. To this end, newly emerged roots of L. sativa were exposed to SPL and its main components (solutions of cyanide, fluoride and aluminum) and to calcium chloride (control) for 48h. After this, root length was measured and cell cycle was examined by means of conventional cytogenetics and immunolocalization. Root growth was inhibited in the treatments with SPL and aluminum; chromosomal and nuclear alterations were observed in all treatments. The immunolocalization evidenced normal dividing cells with regular temporal and spatial distribution of histone H3 phosphorylation at serine 10 (H3S10ph). However, SPL and its main components inhibited the phosphorylation of histone H3 at serine 10, inactivated pericentromeric regions and affected the cohesion of sister chromatids, thus affecting the arrangement of chromosomes in the metaphase plate and separation of chromatids in anaphase. In addition, these substances induced breaks in pericentromeric regions, characterized as fragile sites. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Synthesis of Copper-Chelates Derived from Amino Acids and Evaluation of Their Efficacy as Copper Source and Growth Stimulator for Lactuca sativa in Nutrient Solution Culture.

    Science.gov (United States)

    Kaewchangwat, Narongpol; Dueansawang, Sattawat; Tumcharern, Gamolwan; Suttisintong, Khomson

    2017-11-15

    Five tetradentate ligands were synthesized from l-amino acids and utilized for the synthesis of Cu(II)-chelates 1-5. The efficacy of Cu(II)-chelates as copper (Cu) source and growth stimulator in hydroponic cultivation was evaluated with Lactuca sativa. Their stability test was performed at pH 4-10. The results suggested that Cu(II)-chelate 3 is the most pH tolerant complex. Levels of Cu, Zn, and Fe accumulated in plants supplied with Cu(II)-chelates were compared with those supplied with CuSO 4 at the same Cu concentration of 8.0 μM. The results showed that Cu(II)-chelate 3 significantly enhanced Cu, Zn, and Fe content in shoot by 35, 15, and 48%, respectively. Application of Cu(II)-chelate 3 also improved plant dry matter yield by 54%. According to the results, Cu(II)-chelate 3 demonstrated the highest stimulating effect on plant growth and plant mineral accumulation so that it can be used as an alternative to CuSO 4 for supplying Cu in nutrient solutions and enhancing the plant growth.

  4. Supplemental Upward Lighting from Underneath to Obtain Higher Marketable Lettuce (Lactuca sativa) Leaf Fresh Weight by Retarding Senescence of Outer Leaves.

    Science.gov (United States)

    Zhang, Geng; Shen, Shanqi; Takagaki, Michiko; Kozai, Toyoki; Yamori, Wataru

    2015-01-01

    Recently, the so-called "plant factory with artificial lighting" (PFAL) approach has been developed to provide safe and steady food production. Although PFALs can produce high-yielding and high-quality plants, the high plant density in these systems accelerates leaf senescence in the bottom (or outer) leaves owing to shading by the upper (or inner) leaves and by neighboring plants. This decreases yield and increases labor costs for trimming. Thus, the establishment of cultivation methods to retard senescence of outer leaves is an important research goal to improve PFAL yield and profitability. In the present study, we developed an LED lighting apparatus that would optimize light conditions for PFAL cultivation of a leafy vegetable. Lettuce (Lactuca sativa L.) was hydroponically grown under white, red, or blue LEDs, with light provided from above (downward), with or without supplemental upward lighting from underneath the plant. White LEDs proved more appropriate for lettuce growth than red or blue LEDs, and the supplemental lighting retarded the senescence of outer leaves and decreased waste (i.e., dead or low-quality senescent leaves), leading to an improvement of the marketable leaf fresh weight.

  5. Transformation of Lactuca sativa L. with rol C gene results in increased antioxidant potential and enhanced analgesic, anti-inflammatory and antidepressant activities in vivo.

    Science.gov (United States)

    Ismail, Hammad; Dilshad, Erum; Waheed, Mohammad Tahir; Sajid, Moniba; Kayani, Waqas Khan; Mirza, Bushra

    2016-12-01

    Lettuce is an important edible crop which possesses various medicinal properties. In this study Lactuca sativa L. (cv Grand Rapids) was transformed by Agrobacterium-mediated transformation with rol C gene. Transgene integration and expression was confirmed through PCR and semiquantitative RT-PCR. The transformed extracts were evaluated for their in vitro antioxidant and in vivo analgesic, anti-inflammatory and antidepressant activities in rats. The transformed plants showed 53-98 % increase in total phenolic and 45-58 % increase in total flavonoid contents compared with untransformed plants. Results of total reducing power and total antioxidant capacity exhibited 90-118 and 61-75 % increase in transformed plants, respectively. In contrast to control, DPPH, lipid peroxidation and DNA protection assay showed up to 37, 20 and 50 % enhancement in transformed plants, respectively. The extracts showed similar but significant enhancement behavior in hot plate analgesic and carrageenan-induced hind paw edema test. The transformed extracts showed 72.1 and 78.5 % increase for analgesic and anti-inflammatory activities, respectively. The transformants of rol C gene exhibited prominent antidepressant activity with 64-73 % increase compared with untransformed plants. In conclusion, the present work suggests that transformation with rol C gene can be used to generate lettuce with enhanced medicinally important properties, such as antioxidant, analgesic, anti-inflammatory and antidepressant potential.

  6. Allelopathic effects of aqueous extracts of leaves of tree marigold (Tithonia diversifolia (Hemsl. A. Gray on seed germination and seedling growth of lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    José Alberto Laynez Garsaball

    2013-09-01

    Full Text Available Some chemical compounds released by plants can to control the presence of other plants in their environment both of their own species and different ones, allelopathy is an important factor in regulating the structure of plant communities, a better understanding of these relationships is critical for appropriate agricultural development. The objective was to determine the effects of aqueous extracts of leaves of tree marigold (Tithonia diversifolia on seed germination and seedling growth of lettuce (Lactuca sativa L. cultivar Parris Island. A 15% w/v extract was prepared with leaves of tree marigold gold, it was allowed to stand for 48 h. After, diluting extracts at 0.5, 1.0, 1.5 and 2.0% w/v were obtained and pH and electrical conductivity (S.cm-1 were determined. Sowing was carried out in trays covered with a double layer of absorbent paper on which were placed 25 seeds/tray. Irrigation was applied twice per day using leaf extracts. The control treatment received tap water. A randomized complete block design was used with four replications. Seedlings were harvested at 14 days after sowing. pH decreased and electrical conductivity increased with increases in the concentration of leaf extracts. The germination was negatively affected by extracts. A lowering effect was observed on the overall growth of lettuce seedlings.

  7. Bioactive compounds and antifungal activity of three different seaweed species Ulva lactuca, Sargassum tenerrimum and Laurencia obtusa collected from Okha coast, Western India

    Directory of Open Access Journals (Sweden)

    Megha Barot

    2016-04-01

    Full Text Available Objective: To evaluate bioactive compounds responsible for antifungal activity from seaweeds of Okha coast, Western India. Methods: Each species were extracted with different solvents with increasing polarity: hexane, ethyl acetate, chloroform and methanol using Soxhlet apparatus. The antifungal activity was determined by agar diffusion plate method by using fluconazole, ketoconazole and amphotericin B as standards. Gas chromatography-mass spectrometer analysis was done for identification of bioactive compounds present in crude extract. Results: The gas chromatography-mass spectrometer analysis of all the extracts revealed the presence of steroids, fatty acids and esters compounds. Among the three species, the maximum crude extract yield (53.46% and the largest inhibition zone (36 mm were recorded in methanol extract of Ulva lactuca, whereas the minimum crude extract yield and inhibition zone were recorded in chloroform extract of the same species as 0.5% and 10 mm, respectively. Methanol and ethyl acetate extract showed the maximum antifungal activity and the major important compounds like steroids, fatty acids and esters were detected with higher amount in all the extracts. Conclusions: The present study revealed that the different seaweed extracts showed moderate to significant antifungal activity against the strains tested as compared with the standard fungicides, and polar solvents methanol and ethyl acetate were comparatively efficient for extraction of different metabolites that are responsible for antifungal activity.

  8. Efeito do cultivo orgânico e convencional sobre a vida-de-prateleira de alface americana (Lactuca sativa L. minimamente processada

    Directory of Open Access Journals (Sweden)

    Mello Júlio César

    2003-01-01

    Full Text Available A alface americana (Lactuca sativa, minimamente processada, foi avaliada quanto aos efeitos dos diferentes sistemas de cultivo (orgânico e convencional, sobre a vida-de-prateleira. A alface minimamente processada foi embalada em sacos de polietileno de baixa densidade (PEBD, armazenada em refrigerador a 4masculineC e avaliada até o final da vida-de-prateleira, estabelecida por métodos sensoriais. As avaliações foram realizadas durante a estocagem, nas condições pré-estabelecidas. Nos tempos zero a dez dias, uma equipe sensorial treinada avaliou a alface quanto a: cor, brilho, escurecimento enzimático, aroma, odor estranho, textura e sabor (escores de zero a dez. O teste sensorial determinou que o escore seis (6 eliminaria a amostra; a alface orgânica, atingiu o escore mínimo em tempo superior ao da alface convencional, tendo sido sensivelmente superior a esta em todos os atributos testados.

  9. Electronic Cigarettes

    Science.gov (United States)

    ... New FDA Regulations Text Size: A A A Electronic Cigarettes Electronic cigarettes (e-cigarettes) are battery operated products designed to ... more about: The latest news and events about electronic cigarettes on this FDA page Electronic cigarette basics on ...

  10. Pantoea rodasii sp. nov., Pantoea rwandensis sp. nov. and Pantoea wallisii sp. nov., isolated from Eucalyptus.

    Science.gov (United States)

    Brady, Carrie L; Cleenwerck, Ilse; van der Westhuizen, Lorinda; Venter, Stephanus N; Coutinho, Teresa A; De Vos, Paul

    2012-07-01

    Several Gram-negative-staining, facultatively anaerobic bacterial isolates were obtained from Eucalyptus seedlings showing symptoms of bacterial blight and dieback in Colombia, Rwanda and South Africa. Partial 16S rRNA gene sequencing, together with partial gyrB sequencing, placed the isolates in the genus Pantoea and indicated that they constituted three novel species. Multilocus sequence analysis (MLSA) based on partial sequences of gyrB, rpoB, infB and atpD revealed Pantoea dispersa, Pantoea eucrina and Pantoea cypripedii as their closest phylogenetic relatives. DNA-DNA hybridization studies confirmed the classification of the new isolates as three novel species and phenotypic tests allowed them to be differentiated from their closest phylogenetic neighbours. The names Pantoea rodasii sp. nov. [type strain LMG 26273(T)=BD 943(T) (deposited with the Plant Pathogenic and Plant Protecting Bacteria Collection, South Africa)=BCC 581(T) (deposited with the Bacterial Culture Collection, Forestry and Agricultural Institute, South Africa)], Pantoea rwandensis sp. nov. (type strain LMG 26275(T)=BD 944(T)=BCC 571(T)) and Pantoea wallisii sp. nov. (type strain LMG 26277(T)=BD 946(T)=BCC 682(T)) are proposed.

  11. An atomic model of HIV-1 capsid-SP1 reveals structures regulating assembly and maturation.

    Science.gov (United States)

    Schur, Florian K M; Obr, Martin; Hagen, Wim J H; Wan, William; Jakobi, Arjen J; Kirkpatrick, Joanna M; Sachse, Carsten; Kräusslich, Hans-Georg; Briggs, John A G

    2016-07-29

    Immature HIV-1 assembles at and buds from the plasma membrane before proteolytic cleavage of the viral Gag polyprotein induces structural maturation. Maturation can be blocked by maturation inhibitors (MIs), thereby abolishing infectivity. The CA (capsid) and SP1 (spacer peptide 1) region of Gag is the key regulator of assembly and maturation and is the target of MIs. We applied optimized cryo-electron tomography and subtomogram averaging to resolve this region within assembled immature HIV-1 particles at 3.9 angstrom resolution and built an atomic model. The structure reveals a network of intra- and intermolecular interactions mediating immature HIV-1 assembly. The proteolytic cleavage site between CA and SP1 is inaccessible to protease. We suggest that MIs prevent CA-SP1 cleavage by stabilizing the structure, and MI resistance develops by destabilizing CA-SP1. Copyright © 2016, American Association for the Advancement of Science.

  12. Electronic technology

    International Nuclear Information System (INIS)

    Kim, Jin Su

    2010-07-01

    This book is composed of five chapters, which introduces electronic technology about understanding of electronic, electronic component, radio, electronic application, communication technology, semiconductor on its basic, free electron and hole, intrinsic semiconductor and semiconductor element, Diode such as PN junction diode, characteristic of junction diode, rectifier circuit and smoothing circuit, transistor on structure of transistor, characteristic of transistor and common emitter circuit, electronic application about electronic equipment, communication technology and education, robot technology and high electronic technology.

  13. The Electron

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, George

    1972-01-01

    Electrons are elementary particles of atoms that revolve around and outside the nucleus and have a negative charge. This booklet discusses how electrons relate to electricity, some applications of electrons, electrons as waves, electrons in atoms and solids, the electron microscope, among other things.

  14. Hard electronics; Hard electronics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Hard material technologies were surveyed to establish the hard electronic technology which offers superior characteristics under hard operational or environmental conditions as compared with conventional Si devices. The following technologies were separately surveyed: (1) The device and integration technologies of wide gap hard semiconductors such as SiC, diamond and nitride, (2) The technology of hard semiconductor devices for vacuum micro- electronics technology, and (3) The technology of hard new material devices for oxides. The formation technology of oxide thin films made remarkable progress after discovery of oxide superconductor materials, resulting in development of an atomic layer growth method and mist deposition method. This leading research is expected to solve such issues difficult to be easily realized by current Si technology as high-power, high-frequency and low-loss devices in power electronics, high temperature-proof and radiation-proof devices in ultimate electronics, and high-speed and dense- integrated devices in information electronics. 432 refs., 136 figs., 15 tabs.

  15. DISTRIBUSI Solen sp DI PERAIRAN KABUPATEN BANGKALAN

    Directory of Open Access Journals (Sweden)

    Eva Ari Wahyuni

    2016-03-01

    Full Text Available DISTRIBUTION OF Solen sp IN BANGKALAN WATERSSolen sp potential needs to be developed on the island of Madura, particularly in Bangkalan. Solen sp utilization has increased which has the potential to overfishing. Therefore, this study aims to determine the density of Solen sp and their ecology in the waters Modung village, Modung District, Bangkalan. The experiment was conducted in April 2015 using the descriptive method. The materials used include Solen sp and physico-chemical parameters of the environment (temperature, salinity, pH, and substrate. The analyzes were conducted at the Laboratory of Marine Science, Department of Marine Sciences, Trunojoyo University of Madura by using the tool grabsampler, sieveshaker, and pipetting with gravimetric method. The analysis shows the range of values of temperature between 29-300C, salinity between 31-32 ppt, pH were 7.9-8.0 and the type of substrate in the form of sandy mud, as well as the density of Solen sp from 8-10 individuals/m2. All measurement results indicate normal conditions and in accordance with the sea water quality standard for marine life, which can be a suitable habitat for the growth and development of Solen sp. This condition is thought to affect the density of Solen sp.Keywords: Bangkalan, density, distribution, Solen sp, substrate.ABSTRAKPotensi Solen sp perlu dikembangkan di pulau Madura, khususnya di Kabupaten Bangkalan. Pemanfaatan Solen sp mengalami peningkatan sehingga berpotensi overfishing. Untuk itu, penelitian ini bertujuan untuk mengetahui kepadatan Solen sp dan ekologinya di perairan desa Modung, Kecamatan Modung, Kabupaten Bangkalan. Penelitian dilaksanakan pada bulan April 2015 dengan metode deskriptif. Materi dan bahan yang digunakan diantaranya Solen sp dan parameter fisika-kimia lingkungan (suhu, salinitas, pH, dan substrat. Analisa dilakukan di Laboratorium Ilmu Kelautan, Program studi/Jurusan Ilmu Kelautan Universitas Trunojoyo Madura dengan menggunakan alat

  16. Especificidad del hongo micorrizico (Rhizoctonia sp.) en Phalaenopsis sp., Cymbidium sp., Trichoceros antenifer, Oncidium excavatum, y Cyrtochilum sp.

    OpenAIRE

    Ordoñez, Silvia L.; Pillacela Zhunio, Dora Priscila; Salazar, Jazmín M.; Peña Tapia, Denisse Fabiola

    2016-01-01

    Las orquídeas producen abundantes semillas pequeñas, careciendo de endospermo, cotiledones y sustancias de reserva para llevar a cabo su germinación. Es por esto que estratégicamente las semillas establecen una relación simbiótica con un hongo micorrízico que favorece a su germinación y desarrollo. El objetivo de este estudio fue determinar la especificidad del hongo micorrízico (Rhizoctonia sp.) en la germinación de cinco géneros de orquídeas. Se usaron dos medios de cultivo: 1) PhytamaxTM y...

  17. The family Lohmanniidae (Acari, Oribatida) II: two new Oribatid mites, Meristacarus perikopesis sp. n. from Costa Rica and Torpacarus eidikoterai sp. n. from Kenya.

    Science.gov (United States)

    Fernandez, Nestor; Theron, Pieter; Leiva, Sergio; Jordaan, Anine

    2018-01-01

    Two very particular new species of the family Lohmanniidae were studied and described using optical and Scanning Electron Microscopy (SEM). Meristacarus perikopesis sp. n. displays complex cuticular microsculpture with cross-shaped grooves and pusticulate porose areas; ten transversal bands, with reticulate-foveate microsculpture; S 4 , S 5 , S 7 , S 10 not crossing medial notogastral plane, amongst other characters. Torpacarus eidikoterai sp. n. with: prodorsum - rostrum weakly bilobate with small central structure and CSO present. Six transversal depressions present, transversal bands absent; but six transversal depressions present, none of the depressions crossing medial notogastral plane.

  18. Rodentibacter gen. nov including Rodentibacter pneumotropicus comb. nov., Rodentibacter heylii sp nov., Rodentibacter myodis sp nov., Rodentibacter ratti sp nov., Rodentibacter heidelbergensis sp nov., Rodentibacter trehalosifermentans sp nov., Rodentibacter rarus sp nov., Rodentibacter mrazii

    DEFF Research Database (Denmark)

    Adhikary, Sadhana; Nicklas, Werner; Bisgaard, Magne

    2017-01-01

    genomic comparison allowed the estimation of DNA–DNA renaturation. Rodentibacter heylii sp. nov. was proposed for a group that included the biovar Heyl of [ Pasteurella ] pneumotropica with the type strain ATCC 12555T (=CCUG 998T). A group was proposed as Rodentibacter ratti sp. nov., which included...

  19. Electron radiography

    Science.gov (United States)

    Merrill, Frank E.; Morris, Christopher

    2005-05-17

    A system capable of performing radiography using a beam of electrons. Diffuser means receive a beam of electrons and diffuse the electrons before they enter first matching quadrupoles where the diffused electrons are focused prior to the diffused electrons entering an object. First imaging quadrupoles receive the focused diffused electrons after the focused diffused electrons have been scattered by the object for focusing the scattered electrons. Collimator means receive the scattered electrons and remove scattered electrons that have scattered to large angles. Second imaging quadrupoles receive the collimated scattered electrons and refocus the collimated scattered electrons and map the focused collimated scattered electrons to transverse locations on an image plane representative of the electrons' positions in the object.

  20. Xylanolytic enzyme systems in Arthrobacter sp MTCC 5214 and Lactobacillus sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Jalal, T.

    The production of extracellular xylanolytic enzymes such as xylanase, alfa-L-arabinofuranosidase (alfa-l-AFase), and acetyl xylan esterase (Axe) by marine Arthrobacter sp and Lactobacillus sp was investigated using different carbon sources Induction...

  1. Evaluation of antioxidant and cytotoxic properties of Cynobacteria, Limnothrix sp. and Leptolyngbya sp. from Arabian sea

    Digital Repository Service at National Institute of Oceanography (India)

    Anas, A.; Vinothkumar, S.; Gupta, S.; Jasmin, C.; Joseph, V.; Parameswaran, P.S.; Nair, S.

    The hexane fractions of the marine cyanobacteria: Leptolyngbya sp. and Limnothrix sp., collected from Arabian Sea were found to display promising antioxidant properties than their ethyl acetate fraction during radical scavenging ABTS/DPPH assays (IC...

  2. Cytological Evidence of an Active Role of Silicon in Wheat Resistance to Powdery Mildew (Blumeria graminis f. sp. tritici).

    Science.gov (United States)

    Bélanger, R R; Benhamou, Nicole; Menzies, J G

    2003-04-01

    ABSTRACT Silicon (Si) amendments in the form of exogenously supplied nutrient solution or calcium silicate slag protect wheat plants from powdery mildew disease caused by the fungus Blumeria graminis f. sp. tritici. The most striking difference between Si- and Si+ plants challenged with B. graminis f. sp. tritici was the extent of epidermal cell infection and colonization by B. graminis f. sp. tritici. Histological and ultrastructural analyses revealed that epidermal cells of Si+ plants reacted to B. graminis f. sp. tritici attack with specific defense reactions including papilla formation, production of callose, and release of electron-dense osmiophilic material identified by cytochemical labeling as glycosilated phenolics. Phenolic material not only accumulated along the cell wall but also was associated with altered integrity of haustoria in a manner similar to localized phytoalexins as reported from other pathosystems. These results strongly suggest that Si mediates active localized cell defenses against B. graminis f. sp. tritici attack.

  3. First report of Anisakis sp. in Epinephelus sp. in East Indonesia

    OpenAIRE

    Annytha Ina Rohi Detha; Diana Agustiani Wuri; Julianty Almet; Yuni Riwu; Christin Melky

    2018-01-01

    Objective: The present research was conducted to identify the prevalence of Anisakis sp. as fish-borne zoonoses in Epinephelus sp. in territorial waters of East Nusa Tenggara, Indonesia. Materials and methods: A total of 50 fish (Epinephelus sp.) were collected from Kupang Fish Market in East Nusa Tenggara. Identification of Anisakis sp. was performed based on morphological observations considering shape of ventriculus, boring tooth, and mucron using binocular microscope. Results: Prev...

  4. Determination of the sp(3) C content of a-C films through EELS analysis in the TEM

    NARCIS (Netherlands)

    Galvan, D; Pei, Y.T.; De Hosson, JTM; Cavaleiro, A.

    2005-01-01

    Electron energy loss spectroscopy (EELS) in a transmission electron microscope (TEM) was employed to estimate the sp(3) C content in magnetron sputtered H-free a-C coatings. The deconvolution procedure developed reduces considerably the error which is due to beam point spread function and sample

  5. Nanostructured sp2-carbon infiltration of mesoporous silicon layers.

    Science.gov (United States)

    Polini, Riccardo; Valentini, Veronica; Mattei, Giorgio

    2009-06-01

    The preparation of composite layers made of porous silicon (PS) infiltrated with nanostructured carbon is reported. These composite layers were obtained by chemical vapor infiltration (CVI) of mesoporous silicon under process conditions normally employed to grow diamond films by Hot Filament Chemical Vapour Deposition (HFCVD). Micro-Raman spectroscopy and Field Emission Gun Scanning Electron Microscopy (FEG-SEM) techniques showed that diamond nucleation density was very low whilst sp2 carbon permeated completely, even after 1 h deposition, the thickness of the PS layers that preserved their mesoporous columnar structure.

  6. Isolation and Characterization of a Cyclohexane-Metabolizing Xanthobacter sp.

    Science.gov (United States)

    Trower, M K; Buckland, R M; Higgins, R; Griffin, M

    1985-05-01

    An unusual Xanthobacter sp., capable of independent growth on cyclohexane as the sole source of carbon and energy, has been isolated from soil by using classical enrichment techniques. The mean generation time for growth on cyclohexane was 6 h. The microorganism showed a limited ability to utilize hydrocarbons, with only alicyclic hydrocarbons closely related to cyclohexane supporting growth. Ultrastructural studies indicated the presence of electron-transparent vesicles in the cyclohexane-grown Xanthobacter sp., but the presence of complex intracytoplasmic membranes could not be identified. A soluble inducible enzyme capable of oxidizing cyclohexane was identified in cell extracts. This enzyme had a pH optimum of 6.5, an absolute specificity for NADPH, and a stoichiometric requirement for molecular O(2) which was consistent with the formation of cyclohexanol. The enzyme showed no activity towards straight chain alkanes and only a limited activity towards unsaturated ring compounds. Enzymatic studies with cell extracts have indicated the main route of metabolism of cyclohexane by this Xanthobacter sp. to proceed via cyclohexane --> cyclohexanol --> cyclohexanone --> 1-oxa-2-oxocycloheptane (epsilon-caprolactone) --> 6-hydroxyhexanoate (6-hydroxycaproate) --> --> adipic acid. Alternative routes involving initial double hydroxylation of the cyclohexane ring may operate fortuituously but are unlikely to represent major pathways for the dissimilation of cyclohexane by this microorganism.

  7. Nematodes from the gulf of California. Part 2. Ceramonema nasobema sp. n. (Nematoda: Ceramonematidae)

    NARCIS (Netherlands)

    Holovachov, O.V.; Mundo-Ocampo, M.; Ley, de I.T.; Ley, de P.

    2008-01-01

    An unusual new ceramonematid, Ceramonema nasobema sp. n., is described using light and scanning electron microscopy. It is particularly characterised by the presence of a perioral tube projecting 5.5-7.0 ¿m anterior to the lips, moderately long body (0.86-1.09 mm), relatively small number of body

  8. OXIDATION OF BIPHENYL BY A MULTICOMPONENT ENZYME SYSTEM FROM PSEUDOMONAS SP. STRAIN LB400

    Science.gov (United States)

    Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of bipheny...

  9. Seaweed extracts and unsaturated fatty acid constituents from the green alga Ulva lactuca as activators of the cytoprotective Nrf2-ARE pathway.

    Science.gov (United States)

    Wang, Rui; Paul, Valerie J; Luesch, Hendrik

    2013-04-01

    Increased amounts of reactive oxygen species (ROS) have been implicated in many pathological conditions, including cancer. The major machinery that the cell employs to neutralize excess ROS is through the activation of the antioxidant-response element (ARE) that controls the activation of many phase II detoxification enzymes. The transcription factor that recognizes the ARE, Nrf2, can be activated by a variety of small molecules, most of which contain an α,β-unsaturated carbonyl system. In the pursuit of chemopreventive agents from marine organisms, we built, fractionated, and screened a library of 30 field-collected eukaryotic algae from Florida. An edible green alga, Ulva lactuca, yielded multiple active fractions by ARE-luciferase reporter assay. We isolated three monounsaturated fatty acid (MUFA) derivatives as active components, including a new keto-type C18 fatty acid (1), the corresponding shorter chain C16 acid (2), and an amide derivative (3) of the C18 acid. Their chemical structures were elucidated by NMR and mass spectrometry. All three contain the conjugated enone motif between C7 and C9, which is thought to be responsible for the ARE activity. Subsequent biological studies focused on 1, the most active and abundant ARE activator isolated. C18 acid 1 induced the expression of ARE-regulated cytoprotective genes, including NAD(P)H:quinone oxidoreductase 1, heme oxygenase 1, thioredoxin reductase 1, both subunits of the glutamate-cysteine ligase (catalytic subunit and modifier subunit), and the cystine/glutamate exchange transporter, in IMR-32 human neuroblastoma cells. Its cellular activity requires the presence of Nrf2 and PI3K function, based on RNA interference and pharmacological inhibitor studies, respectively. Treatment with 1 led only to Nrf2 activation, and not the increase in production of NRF2 mRNA. To test its ARE activity and cytoprotective potential in vivo, we treated mice with a single dose of a U. lactuca fraction that was enriched with

  10. Produção de alface (Lactuca sativa L., em função de diferentes concentrações e tipos de biofertilizantes

    Directory of Open Access Journals (Sweden)

    Thiago Pereira de Sousa

    2014-12-01

    Full Text Available Normal 0 21 false false false PT-BR X-NONE X-NONE A alface (Lactuca sativa L. originou-se de espécies silvestres, ainda atualmente encontradas em regiões de clima temperado, no sul da Europa e na Ásia Ocidental. Objetivou-se com este trabalho, estudar o efeito de diferentes concentrações de urina de vaca e biofertilizante aplicados via foliar na cultura da alface em condições edafoclimáticas do município de Catolé do Rocha-PB. O experimento foi conduzido em condições de campo na estação experimental agroecológica do Campus IV da UEPB. O delineamento experimental utilizado foi em blocos casualisados com 12 tratamentos, no esquema fatorial 6x2, com 4 repetições. Testou-se 06 concentrações de biofertilizante: (C1= 0,0; C2= 10; C3= 20; C4= 30; C5= 40 e C6= 50 m/L planta/vez, respectivamente e aplicação do biofertilizante (T1 e da urina de vaca (T2, na produção da alface. Utilizou-se sementes da cultivar Elba (grupo crespo. Avaliou-se: número de folhas (NF, peso verde da folha (PVF e peso verde da parte aérea (PVPA. As concentrações de biofertilizante se comportaram de maneira semelhante dentro dos tipos de biofertilizante e vice-versa. As plantas de alface Elba submetidas á concentração C3= 20 ml/L planta/vez, na presença de urina de vaca (T2 proporcionaram maiores taxas de desenvolvimento foliar.

  11. A chlorophyll fluorescence analysis of photosynthetic efficiency, quantum yield and photon energy dissipation in PSII antennae of Lactuca sativa L. leaves exposed to cinnamic acid.

    Science.gov (United States)

    Hussain, M Iftikhar; Reigosa, Manuel J

    2011-11-01

    This study investigated the effects of cinnamic acid (CA) on growth, biochemical and physiological responses of Lactuca sativa L. CA (0.1, 0.5, 1.0 and 1.5 mM) treatments decreased plant height, root length, leaf and root fresh weight, but it did not affect the leaf water status. CA treatment (1.5 mM) significantly reduced F(v), F(m), photochemical efficiency of PSII (F(v)/F(m)) and quantum yield of PSII (ΦPSII) photochemistry in L. sativa. The photochemical fluorescence quenching (qP) and non-photochemical quenching (NPQ) were reduced after treatment with 1.5 mM CA. Fraction of photon energy absorbed by PS II antennae trapped by "open" PS II reaction centers (P) was reduced by CA (1.5 mM) while, portion of absorbed photon energy thermally dissipated (D) and photon energy absorbed by PSII antennae and trapped by "closed" PSII reaction centers (E) was increased. Carbon isotope composition ratios (δ(13)C) was less negative (-27.10) in CA (1.5 mM) treated plants as compared to control (-27.61). Carbon isotope discrimination (Δ(13)C) and ratio of intercellular CO(2) concentration (ci/ca) from leaf to air were also less in CA treated plants. CA (1.5 mM) also decreased the leaf protein contents of L. sativa as compared to control. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  12. Impacts of major cations (K(+), Na (+), Ca (2+), Mg (2+)) and protons on toxicity predictions of nickel and cadmium to lettuce (Lactuca sativa L.) using exposure models.

    Science.gov (United States)

    Liu, Yang; Vijver, Martina G; Peijnenburg, Willie J G M

    2014-04-01

    Biotic ligand models (BLM) explicitly accounting for hypothetical interactions with biotic ligands and bioavailability as dictated by water chemistry have been developed for various metals and different organisms. It is only recently that BLMs for plants have received increasing attention. Lettuce is one of the most important vegetable crops in the world. This study investigated the impacts of Ca(2+), Mg(2+), K(+), Na(+) and pH, on acute toxicity of Ni and Cd to butter-head lettuce seedlings (Lactuca sativa L.). 4-day assays with the root elongation inhibition (REI) as the endpoint were performed in hydroponic solutions. Magnesium was found to be the sole cation significantly enhancing the median inhibition concentration (IC50) of Ni(2+) with increasing concentration. By incorporating the competitive effects of Mg(2+), the Ni-toxicity prediction was improved significantly as compared to the total metal model (TMM) and the free ion activity model (FIAM). The conditional stability constants derived from the Ni-BLM were log K MgBL = 2.86, log K NiBL = 5.1, and f NiBL (50%)  = 0.57. A slight downtrend was observed in the 4-d IC50 of Cd(2+) at increasing H(+) concentrations, but this tendency was not consistent and statistically significant (p = 0.07) over the whole range. The overall variations of Cd-toxicity within the tested Na(+), K(+), Ca(2+) and Mg(2+) concentration ranges were relatively small and not statistically significant. 80 % of lettuce REI by Cd could be explained using both TMM and FIAM instead of BLM in the present study. Thus, the mechanistically underpinned models for soil quality guidelines should be developed on a metal-specific basis across different exposure conditions.

  13. The use of nile tilapia ( Oreochromis niloticus) cultivation wastewater for the production of romaine lettuce ( Lactuca sativa L. var. longifolia) in water recirculation system

    Science.gov (United States)

    Effendi, Hefni; Wahyuningsih, Sri; Wardiatno, Yusli

    2017-10-01

    In the recirculation aquaponic system (RAS), fish farming waste was utilized as a nutrient for plant, minimizing the water need, reducing the waste disposal into the environment, and producing the fish and plant as well. The study aimed to examine the growth of romaine lettuce ( Lactuca sativa L. var. Longifolia) in aquaponic system without the addition of artificial nutrient. The nutrient relies solely on wastewater of nile tilapia ( Oreochromis niloticus) cultivation circulated continuously on the aquaponic system. The results showed that tilapia weight reached 48.49 ± 3.92 g of T3 (tilapia, romaine lettuce, and inoculated bacteria), followed by T2 (tilapia and romaine lettuce) and T1 (tilapia) of 47.80 ± 1.97 and 45.89 ± 1.10 g after 35 days of experiment. Tilapia best performance in terms of growth and production occurred at T3 of 3.96 ± 0.44 g/day, 12.10 ± 0.63 %/day, 96.11 ± 1.44 % and 1.60 ± 0.07 for GR, SGR, SR, and FCR, respectively. It is also indicated by better water quality characteristic in this treatment. Romaine lettuce harvests of T2 and T3 showed no significant difference, with the final weight of 61.87 ± 5.59 and 57.74 ± 4.35 g. Overall, the integration of tilapia fish farming and romaine lettuce is potentially a promising aquaponic system for sustainable fish and horticulture plant production.

  14. Arabidopsis R2R3-MYB transcription factor AtMYB60 functions as a transcriptional repressor of anthocyanin biosynthesis in lettuce (Lactuca sativa).

    Science.gov (United States)

    Park, Jong-Sug; Kim, Jung-Bong; Cho, Kang-Jin; Cheon, Choong-Ill; Sung, Mi-Kyung; Choung, Myoung-Gun; Roh, Kyung-Hee

    2008-06-01

    The MYB transcription factors play important roles in the regulation of many secondary metabolites at the transcriptional level. We evaluated the possible roles of the Arabidopsis R2R3-MYB transcription factors in flavonoid biosynthesis because they are induced by UV-B irradiation but their associated phenotypes are largely unexplored. We isolated their genes by RACE-PCR, and performed transgenic approach and metabolite analyses in lettuce (Lactuca sativa). We found that one member of this protein family, AtMYB60, inhibits anthocyanin biosynthesis in the lettuce plant. Wild-type lettuce normally accumulates anthocyanin, predominantly cyanidin and traces of delphinidin, and develops a red pigmentation. However, the production and accumulation of anthocyanin pigments in AtMYB60-overexpressing lettuce was inhibited. Using RT-PCR analysis, we also identified the complete absence or reduction of dihydroflavonol 4-reductase (DFR) transcripts in AtMYB60- overexpressing lettuce (AtMYB60-117 and AtMYB60-112 lines). The correlation between the overexpression of AtMYB60 and the inhibition of anthocyanin accumulation suggests that the transcription factorAtMYB60 controls anthocyanin biosynthesis in the lettuce leaf. Clarification of the roles of the AtMYB60 transcription factor will facilitate further studies and provide genetic tools to better understand the regulation in plants of the genes controlled by the MYB-type transcription factors. Furthermore, the characterization of AtMYB60 has implications for the development of new varieties of lettuce and other commercially important plants with metabolic engineering approaches.

  15. Leaf Morphology, Photosynthetic Performance, Chlorophyll Fluorescence, Stomatal Development of Lettuce (Lactuca sativa L.) Exposed to Different Ratios of Red Light to Blue Light.

    Science.gov (United States)

    Wang, Jun; Lu, Wei; Tong, Yuxin; Yang, Qichang

    2016-01-01

    Red and blue light are both vital factors for plant growth and development. We examined how different ratios of red light to blue light (R/B) provided by light-emitting diodes affected photosynthetic performance by investigating parameters related to photosynthesis, including leaf morphology, photosynthetic rate, chlorophyll fluorescence, stomatal development, light response curve, and nitrogen content. In this study, lettuce plants (Lactuca sativa L.) were exposed to 200 μmol⋅m(-2)⋅s(-1) irradiance for a 16 h⋅d(-1) photoperiod under the following six treatments: monochromatic red light (R), monochromatic blue light (B) and the mixture of R and B with different R/B ratios of 12, 8, 4, and 1. Leaf photosynthetic capacity (A max) and photosynthetic rate (P n) increased with decreasing R/B ratio until 1, associated with increased stomatal conductance, along with significant increase in stomatal density and slight decrease in stomatal size. P n and A max under B treatment had 7.6 and 11.8% reduction in comparison with those under R/B = 1 treatment, respectively. The effective quantum yield of PSII and the efficiency of excitation captured by open PSII center were also significantly lower under B treatment than those under the other treatments. However, shoot dry weight increased with increasing R/B ratio with the greatest value under R/B = 12 treatment. The increase of shoot dry weight was mainly caused by increasing leaf area and leaf number, but no significant difference was observed between R and R/B = 12 treatments. Based on the above results, we conclude that quantitative B could promote photosynthetic performance or growth by stimulating morphological and physiological responses, yet there was no positive correlation between P n and shoot dry weight accumulation.

  16. A Lettuce (Lactuca sativa) Homolog of Human Nogo-B Receptor Interacts with cis-Prenyltransferase and Is Necessary for Natural Rubber Biosynthesis*

    Science.gov (United States)

    Qu, Yang; Chakrabarty, Romit; Tran, Hue T.; Kwon, Eun-Joo G.; Kwon, Moonhyuk; Nguyen, Trinh-Don; Ro, Dae-Kyun

    2015-01-01

    Natural rubber (cis-1,4-polyisoprene) is an indispensable biopolymer used to manufacture diverse consumer products. Although a major source of natural rubber is the rubber tree (Hevea brasiliensis), lettuce (Lactuca sativa) is also known to synthesize natural rubber. Here, we report that an unusual cis-prenyltransferase-like 2 (CPTL2) that lacks the conserved motifs of conventional cis-prenyltransferase is required for natural rubber biosynthesis in lettuce. CPTL2, identified from the lettuce rubber particle proteome, displays homology to a human NogoB receptor and is predominantly expressed in latex. Multiple transgenic lettuces expressing CPTL2-RNAi constructs showed that a decrease of CPTL2 transcripts (3–15% CPTL2 expression relative to controls) coincided with the reduction of natural rubber as low as 5%. We also identified a conventional cis-prenyltransferase 3 (CPT3), exclusively expressed in latex. In subcellular localization studies using fluorescent proteins, cytosolic CPT3 was relocalized to endoplasmic reticulum by co-occurrence of CPTL2 in tobacco and yeast at the log phase. Furthermore, yeast two-hybrid data showed that CPTL2 and CPT3 interact. Yeast microsomes containing CPTL2/CPT3 showed enhanced synthesis of short cis-polyisoprenes, but natural rubber could not be synthesized in vitro. Intriguingly, a homologous pair CPTL1/CPT1, which displays ubiquitous expressions in lettuce, showed a potent dolichol biosynthetic activity in vitro. Taken together, our data suggest that CPTL2 is a scaffolding protein that tethers CPT3 on endoplasmic reticulum and is necessary for natural rubber biosynthesis in planta, but yeast-expressed CPTL2 and CPT3 alone could not synthesize high molecular weight natural rubber in vitro. PMID:25477521

  17. Effects of microcystin-LR, cylindrospermopsin and a microcystin-LR/cylindrospermopsin mixture on growth, oxidative stress and mineral content in lettuce plants (Lactuca sativa L.).

    Science.gov (United States)

    Freitas, Marisa; Azevedo, Joana; Pinto, Edgar; Neves, Joana; Campos, Alexandre; Vasconcelos, Vitor

    2015-06-01

    Toxic cyanobacterial blooms are documented worldwide as an emerging environmental concern. Recent studies support the hypothesis that microcystin-LR (MC-LR) and cylindrospermopsin (CYN) produce toxic effects in crop plants. Lettuce (Lactuca sativa L.) is an important commercial leafy vegetable that supplies essential elements for human nutrition; thus, the study of its sensitivity to MC-LR, CYN and a MC-LR/CYN mixture is of major relevance. This study aimed to assess the effects of environmentally relevant concentrations (1, 10 and 100 µg/L) of MC-LR, CYN and a MC-LR/CYN mixture on growth, antioxidant defense system and mineral content in lettuce plants. In almost all treatments, an increase in root fresh weight was obtained; however, the fresh weight of leaves was significantly decreased in plants exposed to 100 µg/L concentrations of each toxin and the toxin mixture. Overall, GST activity was significantly increased in roots, contrary to GPx activity, which decreased in roots and leaves. The mineral content in lettuce leaves changed due to its exposure to cyanotoxins; in general, the mineral content decreased with MC-LR and increased with CYN, and apparently these effects are time and concentration-dependent. The effects of the MC-LR/CYN mixture were almost always similar to the single cyanotoxins, although MC-LR seems to be more toxic than CYN. Our results suggest that lettuce plants in non-early stages of development are able to cope with lower concentrations of MC-LR, CYN and the MC-LR/CYN mixture; however, higher concentrations (100 µg/L) can affect both lettuce yield and nutritional quality. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Evaluation of analgesic, anti-inflammatory, anti-depressant and anti-coagulant properties of Lactuca sativa (CV. Grand Rapids) plant tissues and cell suspension in rats.

    Science.gov (United States)

    Ismail, Hammad; Mirza, Bushra

    2015-06-27

    Lactuca sativa (lettuce) has been traditionally used for relieving pain, inflammation, stomach problems including indigestion and lack of appetite. Moreover, the therapeutic significance of L. sativa includes its anticonvulsant, sedative-hypnotic and antioxidant properties. In the present study, the MC (methanol and chloroform; 1:1) and aqueous extracts of seed and leaf along with cell suspension exudate were prepared. These extracts were explored for their analgesic, anti-inflammatory, antidepressant and anticoagulant effects by hot plate analgesic assay; carrageenan induced hind paw edema test, forced swimming test and capillary method for blood clotting respectively in a rat model. The results were analyzed using one-way Analysis of Variance (ANOVA) followed by Turkey multiple comparison test. Interestingly, the extracts and the cell suspension exudate showed dual inhibition by reducing pain and inflammation. The results indicated that the aqueous extracts of leaf exhibited highest analgesic and anti-inflammatory activities followed by leaf MC, cell suspension exudate, seed aqueous and seed MC extracts. The current findings show that aqueous and MC extracts of seed have the least immobility time in the forced swimming test, which could act as an anti-depressant on the central nervous system. The leaf extracts and cell suspension exudate also expressed moderate anti-depressant activities. In anticoagulant assay, the coagulation time of aspirin (positive control) and MC extract of leaf was comparable, suggesting strong anti-coagulant effect. Additionally, no abnormal behavior or lethality was observed in any animal tested. Taken together, L. sativa can potentially act as a strong herbal drug due to its multiple pharmaceutical effects and is therefore of interest in drug discovery and development of formulations.

  19. A lettuce (Lactuca sativa) homolog of human Nogo-B receptor interacts with cis-prenyltransferase and is necessary for natural rubber biosynthesis.

    Science.gov (United States)

    Qu, Yang; Chakrabarty, Romit; Tran, Hue T; Kwon, Eun-Joo G; Kwon, Moonhyuk; Nguyen, Trinh-Don; Ro, Dae-Kyun

    2015-01-23

    Natural rubber (cis-1,4-polyisoprene) is an indispensable biopolymer used to manufacture diverse consumer products. Although a major source of natural rubber is the rubber tree (Hevea brasiliensis), lettuce (Lactuca sativa) is also known to synthesize natural rubber. Here, we report that an unusual cis-prenyltransferase-like 2 (CPTL2) that lacks the conserved motifs of conventional cis-prenyltransferase is required for natural rubber biosynthesis in lettuce. CPTL2, identified from the lettuce rubber particle proteome, displays homology to a human NogoB receptor and is predominantly expressed in latex. Multiple transgenic lettuces expressing CPTL2-RNAi constructs showed that a decrease of CPTL2 transcripts (3-15% CPTL2 expression relative to controls) coincided with the reduction of natural rubber as low as 5%. We also identified a conventional cis-prenyltransferase 3 (CPT3), exclusively expressed in latex. In subcellular localization studies using fluorescent proteins, cytosolic CPT3 was relocalized to endoplasmic reticulum by co-occurrence of CPTL2 in tobacco and yeast at the log phase. Furthermore, yeast two-hybrid data showed that CPTL2 and CPT3 interact. Yeast microsomes containing CPTL2/CPT3 showed enhanced synthesis of short cis-polyisoprenes, but natural rubber could not be synthesized in vitro. Intriguingly, a homologous pair CPTL1/CPT1, which displays ubiquitous expressions in lettuce, showed a potent dolichol biosynthetic activity in vitro. Taken together, our data suggest that CPTL2 is a scaffolding protein that tethers CPT3 on endoplasmic reticulum and is necessary for natural rubber biosynthesis in planta, but yeast-expressed CPTL2 and CPT3 alone could not synthesize high molecular weight natural rubber in vitro. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Calidad microbiológica y parasitológica de lechuga (Lactuca sativa y cilantro (Coriandrum sativum expendidos en la Parroquia Santa Rita, Aragua, Venezuela

    Directory of Open Access Journals (Sweden)

    Nirza Noguera Machado

    2016-10-01

    Full Text Available Las hortalizas aportan grandes beneficios para la salud debido a sus innumerables propiedades alimenticias; sin embargo, existe una gran variedad de factores que ponen en riesgo la calidad sanitaria de las mismas constituyéndose en vehículos para enfermedades de transmisión alimentaria (ETA. Por ello, se decidió evaluar la calidad microbiológica y parasitológica de dos hortalizas, lechuga (Lactuca sativa y cilantro (Coriandrum sativum expendidas en la Parroquia Santa Rita del Municipio Francisco Linares Alcántara (Aragua, Venezuela. Se analizaron un total de 20 muestras, 10 de cilantro y 10 de lechuga; la determinación microbiológica se realizó por la técnica del Número Más Probable y el análisis parasitológico, mediante observación directa, tinción de Kinyoun y la técnica de Faust. Los resultados mostraron la presencia de coliformes totales (1,1x104 NMP/g en el 100 % de las muestras. No se evidenció coliformes fecales en ninguna de las muestras. En relación al análisis parasitológico, se identificaron protozoarios intestinales, con mayor prevalencia de Blastocystis spp. y menor en helmintos. Los resultados demuestran el peligro potencial que representa el consumo de hortalizas frescas contaminadas para la salud pública. Se debe concientizar a la población sobre medidas sanitarias preventivas que deben aplicar antes del consumo e implementar medidas de control que mejoren las condiciones higiénicas en la cadena de comercialización.

  1. Specialised predation by Palpimanus sp. (Araneae: Palpimanidae ...

    African Journals Online (AJOL)

    This is the first detailed report on the natural prey and the prey-capture tactics of a Palpimanus sp. from Entebbe (Uganda). Although this species fed occasionally on insects, its dominant prey in the field was other spiders, especially jumping spiders (Salticidae) and their eggs. Encounters between Palpimanus sp. and ...

  2. Probiotic Lactobacillus sp. inhibit growth, biofilm formation and gene expression of caries-inducing Streptococcus mutans.

    Science.gov (United States)

    Wasfi, Reham; Abd El-Rahman, Ola A; Zafer, Mai M; Ashour, Hossam M

    2018-03-01

    Streptococcus mutans contributes significantly to dental caries, which arises from homoeostasic imbalance between host and microbiota. We hypothesized that Lactobacillus sp. inhibits growth, biofilm formation and gene expression of Streptococcus mutans. Antibacterial (agar diffusion method) and antibiofilm (crystal violet assay) characteristics of probiotic Lactobacillus sp. against Streptococcus mutans (ATCC 25175) were evaluated. We investigated whether Lactobacillus casei (ATCC 393), Lactobacillus reuteri (ATCC 23272), Lactobacillus plantarum (ATCC 14917) or Lactobacillus salivarius (ATCC 11741) inhibit expression of Streptococcus mutans genes involved in biofilm formation, quorum sensing or stress survival using quantitative real-time polymerase chain reaction (qPCR). Growth changes (OD600) in the presence of pH-neutralized, catalase-treated or trypsin-treated Lactobacillus sp. supernatants were assessed to identify roles of organic acids, peroxides and bacteriocin. Susceptibility testing indicated antibacterial (pH-dependent) and antibiofilm activities of Lactobacillus sp. against Streptococcus mutans. Scanning electron microscopy revealed reduction in microcolony formation and exopolysaccharide structural changes. Of the oral normal flora, L. salivarius exhibited the highest antibiofilm and peroxide-dependent antimicrobial activities. All biofilm-forming cells treated with Lactobacillus sp. supernatants showed reduced expression of genes involved in exopolysaccharide production, acid tolerance and quorum sensing. Thus, Lactobacillus sp. can inhibit tooth decay by limiting growth and virulence properties of Streptococcus mutans. © 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  3. Guide til gode spørgeskemaer

    DEFF Research Database (Denmark)

    Olsen, Henning

    Spørgeskemaundersøgelser bliver ofte brugt til at dokumentere forskellige forhold og begrunde politiske beslutninger. Men resultaterne kan være forbundet med stor usikkerhed. Det kræver omhu og stor sproglig formåen at udarbejde spørgeskemaer. Seniorforsker Henning Olsen har i flere år arbejdet med...... viden om, hvordan folk forstår sproglige meddelelser og genkalder sig informationer. I guiden behandles emner som fx styrende problemstillinger og spørgsmåls fokus og neutralitet, formulering af åbne eller lukkede spørgsmål og svarkategorier, tematiske spørgeforløb, aflastning af svarpersoners...

  4. Folhas de alface lisa (Lactuca sativa minimamente processadas armazenadas em atmosfera modificada: análises físicas, químicas e físico-químicas Minimally processed smooth lettuce leaves (Lactuca sativa stored at modified atmosphere: physica, chemical and physico-chemical analysis

    Directory of Open Access Journals (Sweden)

    Ellen M S Menezes

    2005-03-01

    Full Text Available Alfaces (Lactuca sativa cv. lisa, após seleção e pré-lavagem, foram lavadas com água clorada a 5ºC contendo 150ppm de cloro residual livre e pH ajustado para 6.0, enxagüadas e centrifugadas por 8 minutos a 2200rpm. Em seguida, foram acondicionadas em embalagens plásticas de nylon poli 5 camadas, sem e com atmosfera modificada (N2 contendo 20ppm de O2 e no máximo 20ppm umidade e estocadas a 4ºC. Durante 5 dias foram realizadas mensurações de pH, concentração de sólidos solúveis (graus Brix e análises de acidez (mL NaOH 0,1M/100g folhas de alface. Os produtos sofreram acidificação detectável pela diminuição do pH em ambas as atmosferas. O incremento da acidez foi mostrado, sendo os registros maiores para as amostras controle (sem atmosfera modificada, e não ocorreram variações de graus Brix. Os resultados fizeram concluir que avanços tecnológicos vêm sendo alcançados visando melhorar a qualidade e vida-de-prateleira do vegetal.Lettuce (Lactuca sativa cv. smooth, after being selected and washed, was cleaned with chlorine water at 5ºC, with 150ppm of free chlorine and pH adjusted to 6.0, rinsed and centrifuged for 8 minutes at 2200rpm. Right after, the lettuce leaves were packaged in plastic bags made of nylon poli 5 layers, with and without modified atmosphere (N2 having 20ppm of O2 and 20ppm of maximum moisture and stored at 4ºC. During 5 days there were pH, soluble solids concentration measurements and acid analysis (mL NaOH 0,1M/100g lettuce leaves. The products became acid, detectable by a pH decrease in both atmospheres. A raise in acidity was shown, being the highest marks for the control samples (without modified atmosphere and there was no soluble solids variation. Results have shown that technological progress is being reached aiming to improve the vegetable's quality and shelf life.

  5. Listeria floridensis sp. nov., Listeria aquatica sp. nov., Listeria cornellensis sp. nov., Listeria riparia sp. nov. and Listeria grandensis sp. nov., from agricultural and natural environments.

    Science.gov (United States)

    den Bakker, Henk C; Warchocki, Steven; Wright, Emily M; Allred, Adam F; Ahlstrom, Christina; Manuel, Clyde S; Stasiewicz, Matthew J; Burrell, Angela; Roof, Sherry; Strawn, Laura K; Fortes, Esther; Nightingale, Kendra K; Kephart, Daniel; Wiedmann, Martin

    2014-06-01

    Sampling of agricultural and natural environments in two US states (Colorado and Florida) yielded 18 Listeria-like isolates that could not be assigned to previously described species using traditional methods. Using whole-genome sequencing and traditional phenotypic methods, we identified five novel species, each with a genome-wide average BLAST nucleotide identity (ANIb) of less than 85% to currently described species. Phylogenetic analysis based on 16S rRNA gene sequences and amino acid sequences of 31 conserved loci showed the existence of four well-supported clades within the genus Listeria; (i) a clade representing Listeria monocytogenes, L. marthii, L. innocua, L. welshimeri, L. seeligeri and L. ivanovii, which we refer to as Listeria sensu stricto, (ii) a clade consisting of Listeria fleischmannii and two newly described species, Listeria aquatica sp. nov. (type strain FSL S10-1188(T) = DSM 26686(T) = LMG 28120(T) = BEI NR-42633(T)) and Listeria floridensis sp. nov. (type strain FSL S10-1187(T) = DSM 26687(T) = LMG 28121(T) = BEI NR-42632(T)), (iii) a clade consisting of Listeria rocourtiae, L. weihenstephanensis and three novel species, Listeria cornellensis sp. nov. (type strain TTU A1-0210(T) = FSL F6-0969(T) = DSM 26689(T) = LMG 28123(T) = BEI NR-42630(T)), Listeria grandensis sp. nov. (type strain TTU A1-0212(T) = FSL F6-0971(T) = DSM 26688(T) = LMG 28122(T) = BEI NR-42631(T)) and Listeria riparia sp. nov. (type strain FSL S10-1204(T) = DSM 26685(T) = LMG 28119(T) = BEI NR- 42634(T)) and (iv) a clade containing Listeria grayi. Genomic and phenotypic data suggest that the novel species are non-pathogenic. © 2014 IUMS.

  6. IAA-producing Penicillium sp. NICS01 triggers plant growth and suppresses Fusarium sp.-induced oxidative stress in sesame (Sesamum indicum L.).

    Science.gov (United States)

    Radhakrishnan, Ramalingam; Shim, Kang-Bo; Lee, Byeong-Won; Hwang, Chung-Dong; Pae, Suk-Bok; Park, Chang-Hwan; Kim, Sung-Up; Lee, Choon-Ki; Baek, In-Youl

    2013-06-28

    Application of rhizospheric fungi is an effective and environmentally friendly method of improving plant growth and controlling many plant diseases. The current study was aimed to identify phytohormone-producing fungi from soil, to understand their roles in sesame plant growth, and to control Fusarium disease. Three predominant fungi (PNF1, PNF2, and PNF3) isolated from the rhizospheric soil of peanut plants were screened for their growth-promoting efficiency on sesame seedlings. Among these isolates, PNF2 significantly increased the shoot length and fresh weight of seedlings compared with controls. Analysis of the fungal culture filtrate showed a higher concentration of indole acetic acid in PNF2 than in the other isolates. PNF2 was identified as Penicillium sp. on the basis of phylogenetic analysis of ITS sequence similarity. The in vitro biocontrol activity of Penicillium sp. against Fusarium sp. was exhibited by a 49% inhibition of mycelial growth in a dual culture bioassay and by hyphal injuries as observed by scanning electron microscopy. In addition, greenhouse experiments revealed that Fusarium inhibited growth in sesame plants by damaging lipid membranes and reducing protein content. Co-cultivation with Penicillium sp. mitigated Fusarium-induced oxidative stress in sesame plants by limiting membrane lipid peroxidation, and by increasing the protein concentration, levels of antioxidants such as total polyphenols, and peroxidase and polyphenoloxidase activities. Thus, our findings suggest that Penicillium sp. is a potent plant growthpromoting fungus that has the ability to ameliorate damage caused by Fusarium infection in sesame cultivation.

  7. Predictive value of Sp1/Sp3/FLIP signature for prostate cancer recurrence.

    Directory of Open Access Journals (Sweden)

    Roble G Bedolla

    Full Text Available Prediction of prostate cancer prognosis is challenging and predictive biomarkers of recurrence remain elusive. Although prostate specific antigen (PSA has high sensitivity (90% at a PSA level of 4.0 ng/mL, its low specificity leads to many false positive results and considerable overtreatment of patients and its performance at lower ranges is poor. Given the histopathological and molecular heterogeneity of prostate cancer, we propose that a panel of markers will be a better tool than a single marker. We tested a panel of markers composed of the anti-apoptotic protein FLIP and its transcriptional regulators Sp1 and Sp3 using prostate tissues from 64 patients with recurrent and non-recurrent cancer who underwent radical prostatectomy as primary treatment for prostate cancer and were followed with PSA measurements for at least 5 years. Immunohistochemical staining for Sp1, Sp3, and FLIP was performed on these tissues and scored based on the proportion and intensity of staining. The predictive value of the FLIP/Sp1/Sp3 signature for clinical outcome (recurrence vs. non-recurrence was explored with logistic regression, and combinations of FLIP/Sp1/Sp3 and Gleason score were analyzed with a stepwise (backward and forward logistic model. The discrimination of the markers was identified by sensitivity-specificity analysis and the diagnostic value of FLIP/Sp1/Sp3 was determined using area under the curve (AUC for receiver operator characteristic curves. The AUCs for FLIP, Sp1, Sp3, and Gleason score for predicting PSA failure and non-failure were 0.71, 0.66, 0.68, and 0.76, respectively. However, this increased to 0.93 when combined. Thus, the "biomarker signature" of FLIP/Sp1/Sp3 combined with Gleason score predicted disease recurrence and stratified patients who are likely to benefit from more aggressive treatment.

  8. Roles of natural zeolite (clinoptiolite) as a bed medium on growth and body composition of red tilapia (Oreochromis sp.) and lettuce (Lactuca sativa var longifolia) seedlings in a pisciponic system

    OpenAIRE

    Rafiee, Gh.R.; Saad, Ch.R.

    2008-01-01

    Natural zeolite was used as a bed medium for plantation of lettuce seedlings and its effects on growth and chemical composition of red tilapia and lettuce were investigated in a pisciponic system. The place of study was the Aquatic Resources Technology Laboratory, Faculty of Agriculture, at the University Putra Malaysia, in 2002. The mean individual weight and biomass of fish in the treatment with zeolite were significantly higher (P

  9. Parallelization of ITS on an IBM SP2 computer

    International Nuclear Information System (INIS)

    Monte Carlo simulation of complex phenomena that occur in coupled electron-photon radiation transport can tax even the most powerful serial computers. Depending on the number of materials and the required resolution, there is a need to use up to millions of histories to adequately represent three-dimensional transport. The greatest limitation of most Monte Carlo simulations is the large computational time and computing memory required for very large scale problems. Emergence of new parallel computers, such as the IBM SP2, may lessen this difficulty for radiation transport simulation. This study presents the implementation of the Integrated Tiger Series, (ITS) of codes on the IBM SP2 using the PVMe message-passing library to achieve parallel efficiencies as high as 98% on eight computer nodes. ITS is a general purpose state-of-the-art Monte Carlo method for solving linear, time-independent, coupled electron-photon radiation transport problems with or without the presence of external electric and magnetic fields. A batch decomposition approach has been taken toward parallelization of the code. In ITS, the particle histories are divided into open-quotes batchesclose quotes of equal size and the evaluation of the estimated quantities are performed using batch-averaged sample statistics

  10. Bioremediation: Copper Nanoparticles from Electronic-waste

    OpenAIRE

    D. R. MAJUMDER

    2012-01-01

    A single-step eco-friendly approach has been employed to synthesize copper nanoparticles. The superfast advancement in the field of electronics has given rise to a new type of waste called electronic waste. Since the physical and chemical recycling procedures have proved to be hazardous, the present work aims at the bioremediation of e-waste in order to recycle valuable metals. Microorganisms such as Fusarium oxysporum and Pseudomonas sp. were able to leach copper (84-130 nm) from integrated ...

  11. Electron detector

    International Nuclear Information System (INIS)

    Hashimoto, H.; Mogami, A.

    1975-01-01

    A device for measuring electron densities at a given energy level in an electron beam or the like having strong background noise, for example, in the detection of Auger electric energy spectrums is described. An electron analyzer passes electrons at the given energy level and at the same time electrons of at least one adjacent energy level. Detecting means associated therewith produce signals indicative of the densities of the electrons at each energy level and combine these signals to produce a signal indicative of the density of the electrons of the given energy level absent background noise

  12. Green Synthesis Nanoparticle ZnO Sargassum sp. Extract and The Products Charactheristic

    OpenAIRE

    Rodiah Nurbaya Sari; N. Nurhasni; M. Ainul Yaqin

    2017-01-01

    The synthesis of zinc oxide (ZnO) nanoparticles is an emerging research area due to its wide range of applications, such as electronics, pharmaceuticals, optics and food packaging. In this study, described the green synthesis of ZnO nanoparticles and their characteristics using Sargassum sp. extract and 0.1 M zinc nitrate as the precursors. The variations include Sargassum sp. extracts volume of 5, 10, and 20mL and the calcination temperature of 400, 500, and 600 oC. The characterization had ...

  13. Antibacterial Actions and Potential Phototoxic Effects of Volatile oils of Foeniculum sp. (fennel, Salvia sp. (sage, Vitis sp. (grape, Lavandula sp. (lavender

    Directory of Open Access Journals (Sweden)

    Elif Ayse Erdogan Eliuz

    2016-09-01

    Full Text Available In the present study, the volatile compounds of essential oil of Foeniculum vulgare (fennel, Salvia officinalis (sage, Vitis vinifera (grape, Lavandula angustifolia (lavender were analysed by gas chromatography-mass spectrometry (GC-MS using the Nist and Willey libraries. It was determined that the main components of Foeniculum sp. were anethole (41.11%, carvacrol (9.18%. whereas main components of Salvia sp were 1.8 cineole (34.09%, caryophyllene (10.95%, camphor (9.44%, α-pinene (8.42%. Vitis sp. contained linoleic acid (36.98%, 2,4-decadienal (30.79%. Finally, volatile component of Lavandula sp. was linalool (33.57%, linalyl acetate (30.74%. Photoxic antibacterial activity of volatile oil of those plants against Escherichia coli (ATCC 25293, Klebsiella pneumoniae (10031, Salmonella thyphimurium, Bacillus subtilis (ATCC 6633, Staphylococcus aureus (ATCC 25925, Enterococcus feacalis (ATCC 29212 were examined by using disc diffusion method. We demonstrated that volatile oil effectively can be activated by a standard LED light. In vitro, significant phototoxicity was demonstrated by volatile oil of Foeniculum sp. and Vitis sp. (P < 0.05, while minor phototoxicity was induced by Lavandula sp. Therefore, volatile oil of plant can be considered as a potential photosensitizer in the photochemical therapy.

  14. Production and characterization of a biosurfactant produced by Streptomyces sp. DPUA 1559 isolated from lichens of the Amazon region.

    Science.gov (United States)

    Santos, A P P; Silva, M D S; Costa, E V L; Rufino, R D; Santos, V A; Ramos, C S; Sarubbo, L A; Porto, A L F

    2017-12-11

    Surfactants are amphipathic compounds containing both hydrophilic and hydrophobic groups, capable to lower the surface or interfacial tension. Considering the advantages of the use of biosurfactants produced by microorganisms, the aim of this paper was to develop and characterize a biosurfactant produced by Streptomyces sp. DPUA1559 isolated from lichens of the Amazon region. The microorganism was cultured in a mineral medium containing 1% residual frying soybean oil as the carbon source. The kinetics of biosurfactant production was accompanied by reducing the surface tension of the culture medium from 60 to values around 27.14 mN/m, and by the emulsification index, which showed the efficiency of the biosurfactant as an emulsifier of hydrophobic compounds. The yield of the isolated biosurfactant was 1.74 g/L, in addition to the excellent capability of reducing the surface tension (25.34 mN/m), as observed from the central composite rotational design when the biosurfactant was produced at pH 8.5 at 28°C. The critical micelle concentration of the biosurfactant was determined as 0.01 g/mL. The biosurfactant showed thermal and pH stability regarding the surface tension reduction, and tolerance under high salt concentrations. The isolated biosurfactant showed no toxicity to the micro-crustacean Artemia salina, and to the seeds of lettuce (Lactuca sativa L.) and cabbage (Brassica oleracea L.). The biochemistry characterization of the biosurfactant showed a single protein band, an acid character and a molecular weight around 14.3 kDa, suggesting its glycoproteic nature. The results are promising for the industrial application of this new biosurfactant.

  15. TurboSP and the Topological Trigger

    CERN Document Server

    Belavin, Vladislav

    2016-01-01

    TurboSP was originally proposed as an alternative to Full stream in LHCb data flow. TurboSP is a data flow strategy which not only selects events that should be preserved, like in Full stream, but also provides selective persistence. This is achieved by saving candidates and subset of the reconstruction. During this summer project we investigated the physics viability of using TurboSP with the topological lines and found out a possibility to reduce the number of kept tracks per event by two times while keeping a ratio of fully picked up interesting decay modes on $\\sim 97 \\%$ level.

  16. Electron/electron acoustic instability

    International Nuclear Information System (INIS)

    Gary, S.P.

    1987-01-01

    The electron acoustic wave becomes a normal mode of an unmagnetized collisionless plasma in the presence of two electron components with similar densities, but strongly disparate temperatures. The characteristic frequency of this mode is the plasma frequency of the cooler electron component. If these two electron components have a relative drift speed several times the thermal speed of the cooler component, the electron/electron acoustic instability may arise. This paper describes the parametric dependences of the threshold drift speed and maximum growth rate of this instability, and compares these with the same properties of the electron/ion acoustic instability. Under the condition of zero current, the electron/ion acoustic instability typically has the lower threshold drift speed, so that observation of the electron/electron acoustic instability is a strong indication of the presence of an electrical current in the plasma

  17. Amphibian (Xenopus sp.) iodothyronine deiodinase ...

    Science.gov (United States)

    The U.S. EPA-MED amphibian thyroid group is currently screening chemicals for inhibition of human iodothyronine deiodinase activity as components of the thyroid system important in human development. Amphibians are a bellwether taxonomic group to gauge toxicity of chemicals in the environment. Amphibian thyroid function is not only important in development but also metamorphosis. Xenopus sp. have been used extensively as model organisms and are well characterized genetically. We propose to screen a list of chemicals (selected from the human DIO screening results) to test for inhibition of Xenopus deiodinases. Large quantities of the enzymes will be produced using an adenovirus system. Our preliminary results show that there may be catalytic differences between human and Xenopus deiodinases. The Twin Ports Early Career Scientists is a new group formed within the Duluth-Superior scientific community. This presentation will provide a basic introduction to my research and our mission at EPA, and help to establish networking and collaboration relationships across disciplines and institutions.

  18. Detection of Salmonella sp., Vibrio sp. and total plate count bacteria on blood cockle (Anadara granosa)

    Science.gov (United States)

    Ekawati, ER; Yusmiati, S. N. H.

    2018-01-01

    Blood cockle (Anadara granosa) has high level of zinc and protein, which is beneficial for therapeutic function for malnourished particularly stunting case in children. Zinc in animal foods is more absorbable than that from vegetable food. Blood cockle (Anadara granosa) is rich in nutrient and an excellent environment for the growth of microorganisms. This research aimed to identify the contamination of Salmonella sp., Vibrio sp. and total plate count bacteria on blood cockle (Anadara granosa). This was observation research with laboratory analysis. Salmonella sp. and Vibrio sp. were detected from blood cockle. Total plate count was determine of the total amount of the bacteria. Results detected from 20 samples of blood cockle showed that all samples were negative of Salmonella sp. and 1 sample positive Vibrio sp. The result of total plate count bacteria was sample.

  19. The allelopathic effects of invasive plant Solidago canadensis on seed germination and growth of Lactuca sativa enhanced by different types of acid deposition.

    Science.gov (United States)

    Wang, Congyan; Xiao, Hongguang; Zhao, Lulu; Liu, Jun; Wang, Lei; Zhang, Fei; Shi, Yanchun; Du, Daolin

    2016-04-01

    Invasive species can exhibit allelopathic effects on native species. Meanwhile, the types of acid deposition are gradually changing. Thus, the allelopathic effects of invasive species on seed germination and growth of native species may be altered or even enhanced under conditions with diversified acid deposition. This study aims to assess the allelopathic effects (using leaves extracts) of invasive plant Solidago canadensis on seed germination and growth of native species Lactuca sativa treated with five types of acid deposition with different SO4(2-) to NO3(-) ratios (1:0, sulfuric acid; 5:1, sulfuric-rich acid; 1:1, mixed acid; 1:5, nitric-rich acid; 0:1, nitric acid). Solidago canadensis leaf extracts exhibited significantly allelopathic effects on germination index, vigor index, and germination rate index of L. sativa. High concentration of S. canadensis leaf extracts also similarly exhibited significantly allelopathic effects on root length of L. sativa. This may be due to that S. canadensis could release allelochemicals and then trigger allelopathic effects on seed germination and growth of L. sativa. Acid deposition exhibited significantly negative effects on seedling biomass, root length, seedling height, germination index, vigor index, and germination rate index of L. sativa. This may be ascribed to the decreased soil pH values mediated by acid deposition which could produce toxic effects on seedling growth. Sulfuric acid deposition triggered more toxic effects on seedling biomass and vigor index of L. sativa than nitric acid deposition. This may be attributing to the difference in exchange capacity with hydroxyl groups (OH(-)) between SO4(2-) and NO3(-) as well as the fertilizing effects mediated by nitric deposition. All types of acid deposition significantly enhanced the allelopathic effects of S. canadensis on root length, germination index, vigor index, and germination rate index of L. sativa. This may be due to the negatively synergistic effects of

  20. Predawn and high intensity application of supplemental blue light decreases the quantum yield of PSII and enhances the amount of phenolic acids, flavonoids, and pigments in Lactuca sativa.

    Science.gov (United States)

    Ouzounis, Theoharis; Razi Parjikolaei, Behnaz; Fretté, Xavier; Rosenqvist, Eva; Ottosen, Carl-Otto

    2015-01-01

    To evaluate the effect of blue light intensity and timing, two cultivars of lettuce [Lactuca sativa cv. "Batavia" (green) and cv. "Lollo Rossa" (red)] were grown in a greenhouse compartment in late winter under natural light and supplemental high pressure sodium (SON-T) lamps yielding 90 (±10) μmol m(-2) s(-1) for up to 20 h, but never between 17:00 and 21:00. The temperature in the greenhouse compartments was 22/11°C day/night, respectively. The five light-emitting diode (LED) light treatments were Control (no blue addition), 1B 06-08 (Blue light at 45 μmol m(-2) s(-1) from 06:00 to 08:00), 1B 21-08 (Blue light at 45 μmol m(-2) s(-1) from 21:00 to 08:00), 2B 17-19 (Blue at 80 μmol m(-2) s(-1) from 17:00 to 19:00), and 1B 17-19 (Blue at 45 μmol m(-2) s(-1) from 17:00 to 19:00). Total fresh and dry weight was not affected with additional blue light; however, plants treated with additional blue light were more compact. The stomatal conductance in the green lettuce cultivar was higher for all treatments with blue light compared to the Control. Photosynthetic yields measured with chlorophyll fluorescence showed different response between the cultivars; in red lettuce, the quantum yield of PSII decreased and the yield of non-photochemical quenching increased with increasing blue light, whereas in green lettuce no difference was observed. Quantification of secondary metabolites showed that all four treatments with additional blue light had higher amount of pigments, phenolic acids, and flavonoids compared to the Control. The effect was more prominent in red lettuce, highlighting that the results vary among treatments and compounds. Our results indicate that not only high light level triggers photoprotective heat dissipation in the plant, but also the specific spectral composition of the light itself at low intensities. However, these plant responses to light are cultivar dependent.

  1. Development and application of a 6.5 million feature Affymetrix Genechip® for massively parallel discovery of single position polymorphisms in lettuce (Lactuca spp.

    Directory of Open Access Journals (Sweden)

    Stoffel Kevin

    2012-05-01

    Full Text Available Abstract Background High-resolution genetic maps are needed in many crops to help characterize the genetic diversity that determines agriculturally important traits. Hybridization to microarrays to detect single feature polymorphisms is a powerful technique for marker discovery and genotyping because of its highly parallel nature. However, microarrays designed for gene expression analysis rarely provide sufficient gene coverage for optimal detection of nucleotide polymorphisms, which limits utility in species with low rates of polymorphism such as lettuce (Lactuca sativa. Results We developed a 6.5 million feature Affymetrix GeneChip® for efficient polymorphism discovery and genotyping, as well as for analysis of gene expression in lettuce. Probes on the microarray were designed from 26,809 unigenes from cultivated lettuce and an additional 8,819 unigenes from four related species (L. serriola, L. saligna, L. virosa and L. perennis. Where possible, probes were tiled with a 2 bp stagger, alternating on each DNA strand; providing an average of 187 probes covering approximately 600 bp for each of over 35,000 unigenes; resulting in up to 13 fold redundancy in coverage per nucleotide. We developed protocols for hybridization of genomic DNA to the GeneChip® and refined custom algorithms that utilized coverage from multiple, high quality probes to detect single position polymorphisms in 2 bp sliding windows across each unigene. This allowed us to detect greater than 18,000 polymorphisms between the parental lines of our core mapping population, as well as numerous polymorphisms between cultivated lettuce and wild species in the lettuce genepool. Using marker data from our diversity panel comprised of 52 accessions from the five species listed above, we were able to separate accessions by species using both phylogenetic and principal component analyses. Additionally, we estimated the diversity between different types of cultivated lettuce and

  2. Peculiarities of forming quality parameters of commercial products of cutting lettuce (Lactuca sativa var. capitata L. depending on the method of cultivation

    Directory of Open Access Journals (Sweden)

    Н. В. Лещук

    2017-06-01

    Full Text Available Purpose. To investigate features of commercial head quality formation in varieties of cutting lettuce (Lactuca sativa var. capitata L. for different growing methods. To study the influence of growing methods for cutting lettuce plants on the weight of commercial heads, indices of yield and quality of freshly harvested products. Methods. Field study, laboratory testing and statistical evaluation. Results. The results of studying peculiarities of head formation in such cutting lettuce varieties as ‘Godar’ (control, ‘Smuhlianka’, ‘Olzhych’ and ‘Dyvohrai’ were shown. Based on the results of phenological observations, the duration of interstage periods of growth and development of cutting lettuce plants was determined for the different growing methods. The model of cutting lettuce of capitata variety for different growing methods was presented in terms of biochemical parameters (content of dry matter, vitamin C, nitrates, amount of sugars. The influence of growing methods for cutting lettuce plants on the commercial head weight, indices of yield and quality of freshly harvested products was studied. Obtained results confirmed that in early ripening varie­ti­es the heads were smaller (150 g and not dense, in late ripening varieties they were large and dense, weight was 150–500 g. Freshly harvested commercial products of head lettuce in case of seedling cultivation was characterized by a slight increase in dry matter content by 0.15–0.29%. The corresponding pattern was observed for the total sugar content. Its amount was slightly higher: 1.3–1.9% in case of direct sowing and 1.6–1.9% – for seedlings cultivation. The content of ascorbic acid (vitamin C, mg/100 g was the highest in the ‘Dyvohrai’ variety despite of the method of growing. The largest quantity of nitrates in lettuce heads was in the inner stem (480 mg/kg, while in the middle of the head it was reduced to 110 mg/kg. Conclusions. Freshly harvested heads of

  3. Effect of aqueous and hydro-alcoholic extracts of lettuce (Lactuca sativa) seed on testosterone level and spermatogenesis in NMRI mice.

    Science.gov (United States)

    Ahangarpour, Akram; Oroojan, Ali Akbar; Radan, Maryam

    2014-01-01

    One of the considerable uses of lettuce (Lactuca sativa) seed in traditional medicine has been to reduce semen, sperm and sexuality. The aim of this study was to investigate the effects of aqueous and hydro-alcoholic extracts of lettuce seed on testosterone level and spermatogenesis. In this experimental study 24 adult male NMRI mice weighing 20-25gr were purchased. Animals were randomly divided into 4 groups: controls, hydro-alcoholic (200 mg/kg) and aqueous extracts (50, 100mg/kg). The extracts were injected intraperitoneally once a day for 10 consecutive days. 2 weeks after the last injection, the mice were anaesthetized by ether and after laparatomy blood was collected from the heart to determine testosterone by ELISA assay kit. Then testis and cauda epididymis of all animals were removed for analyzing testis morphology and sperm count and viability. Testis weight in hydro-alcoholic and aqueous extracts 100 mg/kg (p=0.001) and aqueous extract 50 mg/kg (p=0.008) groups was increased. Sperm viability in hydro-alcoholic (p=0.001) and aqueous extracts 50 (p=0.026), 100 mg/kg (p=0.045) groups was decreased, Also the results showed a significant decrease in sperm count in hydro-alcoholic (p=0.035) and aqueous extracts 50 mg/kg (p=0.006) groups in comparison with control group. Also there was a significant increase in serum level of testosterone in aqueous extract 50 mg/kg group in comparison with control (p=0.002) hydro-alcoholic (p=0.001) and aqueous extracts 100 mg/kg (p=0.003) groups. Present results demonstrated that hydro-alcoholic and aqueous 50 mg/kg extracts of lettuce seed have antispermatogenic effects, also aqueous extract 50 mg/kg increased serum level of testosterone in mice. Therefore we can suggest that lettuce seed could be a potential contraceptive agent. This article extracted from M.Sc. student research project. (Ali Akbar Oroojan).

  4. Influence of season growth, soils and irrigation water composition on the concentration of uranium in two lettuce (Lactuca sativa L.) varieties. Field experiments

    Science.gov (United States)

    Abreu, M. M.; Neves, O.; Marcelino, M.

    2012-04-01

    Former uranium mines areas are frequently the sources of environmental radionuclides problems even many years after the closure of mining operations. A concern for inhabitants from mining areas is the use of contaminated land or irrigation water for agriculture, and the potential transfer of metals from soils to vegetables, and to humans through the food chain. The main aim of this study was to compare the uranium concentration in lettuce (Lactuca sativa L. varieties Marady and Romana) grown in different seasons (autumn and summer) and exposed to high and low uranium concentrations both in irrigation water and agricultural soil. The content of uranium in irrigation water, soil (total and available fraction) and in lettuce leaf samples was analyzed in a certified laboratory. In the field experiments, two agricultural soils were divided into two plots (four replicates each); one of them was irrigated with uranium contaminated water (0.94 to 1.14 mg/L) and the other with uncontaminated water (< 0.02 mg/L). Irrigation with contaminated water together with highest soil uranium available concentration (10 to 13 mg/kg) had negative effects on both studied lettuce varieties, namely yield reduction (up to 53% and 87% in autumn and summer experiments, respectively) and increase of uranium leaf concentration (up to 1.4 and 7 fold in autumn and summer, respectively). Effect on lettuce yield was mainly due to the high soil salinity (1.01 to 6.31 mS/cm) as a consequence of high irrigation water electrical conductivity (up to 1.82 mS/cm) and low lettuce soil salinity tolerance (1 to 3 mS/cm). The highest lettuce uranium concentration (dry weight) observed was 2.13 and 5.37 mg/kg for Marady and Romana variety, respectively. The highest uranium lettuce concentration in Romana variety was also the effect of its growing in summer season when it was subject to greatest frequency and amount of water irrigation. The consumption by an adult of the lettuce that concentrate more uranium

  5. The Rhizoctonia solani AG1-IB (isolate 7/3/14) transcriptome during interaction with the host plant lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Verwaaijen, Bart; Wibberg, Daniel; Kröber, Magdalena; Winkler, Anika; Zrenner, Rita; Bednarz, Hanna; Niehaus, Karsten; Grosch, Rita; Pühler, Alfred; Schlüter, Andreas

    2017-01-01

    The necrotrophic pathogen Rhizoctonia solani is one of the most economically important soil-borne pathogens of crop plants. Isolates of R. solani AG1-IB are the major pathogens responsible for bottom-rot of lettuce (Lactuca sativa L.) and are also responsible for diseases in other plant species. Currently, there is lack of information regarding the molecular responses in R. solani during the pathogenic interaction between the necrotrophic soil-borne pathogen and its host plant. The genome of R. solani AG1-IB (isolate 7/3/14) was recently established to obtain insights into its putative pathogenicity determinants. In this study, the transcriptional activity of R. solani AG1-IB was followed during the course of its pathogenic interaction with the host plant lettuce under controlled conditions. Based on visual observations, three distinct pathogen-host interaction zones on lettuce leaves were defined which covered different phases of disease progression on tissue inoculated with the AG1-IB (isolate 7/3/14). The zones were defined as: Zone 1-symptomless, Zone 2-light brown discoloration, and Zone 3-dark brown, necrotic lesions. Differences in R. solani hyphae structure in these three zones were investigated by microscopic observation. Transcriptional activity within these three interaction zones was used to represent the course of R. solani disease progression applying high-throughput RNA sequencing (RNA-Seq) analysis of samples collected from each Zone. The resulting three transcriptome data sets were analyzed for their highest expressed genes and for differentially transcribed genes between the respective interaction zones. Among the highest expressed genes was a group of not previously described genes which were transcribed exclusively during early stages of interaction, in Zones 1 and 2. Previously described importance of up-regulation in R. solani agglutinin genes during disease progression could be further confirmed; here, the corresponding genes exhibited

  6. Lactucaxanthin - a potential anti-diabetic carotenoid from lettuce (Lactuca sativa) inhibits α-amylase and α-glucosidase activity in vitro and in diabetic rats.

    Science.gov (United States)

    Gopal, Sowmya Shree; Lakshmi, Magisetty Jhansi; Sharavana, Gurunathan; Sathaiah, Gunaseelan; Sreerama, Yadahally N; Baskaran, Vallikannan

    2017-03-22

    Intestinal and pancreatic α-amylase and α-glucosidase inhibitors offer an approach to lower the levels of post-prandial hyperglycemia through the control of dietary starch breakdown in digestion. This study hypothesized that lactucaxanthin (Lxn) in lettuce (Lactuca sativa) inhibits the activity of α-amylase and α-glucosidase. In this study, the interaction of Lxn with α-amylase and α-glucosidase in silico and its inhibitory effect on these enzymes were studied using in vitro and STZ-induced diabetic rat models. Lxn was isolated from lettuce with 96% purity confirmed by HPLC and LCMS. The in silico analysis showed that Lxn has a lower binding energy (-6.05 and -6.34 kcal mol -1 ) with α-amylase and α-glucosidase compared to their synthetic inhibitors, acarbose (-0.21 kcal mol -1 ) and miglitol (-2.78 kcal mol -1 ), respectively. In vitro α-amylase and α-glucosidase inhibition assays revealed that Lxn had IC 50 values of 435.5 μg mL -1 and 1.84 mg mL -1 , but acarbose has values of 2.5 and 16.19 μg mL -1 . The in vivo results showed an increased activity for α-amylase and α-glucosidase in the intestine (4.7 and 1.30 fold, p < 0.05) and pancreas (1.3 and 1.48 fold, p < 0.05) of STZ induced diabetic rats compared to normal rats. Whereas the activity decreased (p < 0.05) in the Lxn fed diabetic rats, except for the intestinal α-glucosidase activity (1.69 ± 0.12 PNP per min per mg protein). This was confirmed by the low blood glucose level (239.4 ± 18.2 mg dL -1 ) in diabetic rats fed Lxn compared to the diabetic group (572.2 ± 30.5 mg dL -1 , p < 0.05). Lxn significantly inhibited (p < 0.05) the activity of α-amylase and α-glucosidase and could be of medical and nutritional relevance in the treatment of diabetes.

  7. Selective toxin effects on faster and slower growing individuals in the formation of hormesis at the population level - A case study with Lactuca sativa and PCIB.

    Science.gov (United States)

    Belz, Regina G; Sinkkonen, Aki

    2016-10-01

    Natural plant populations have large phenotypic plasticity that enhances acclimation to local stress factors such as toxin exposures. While consequences of high toxin exposures are well addressed, effects of low-dose toxin exposures on plant populations are seldom investigated. In particular, the importance of 'selective low-dose toxicity' and hormesis, i.e. stimulatory effects, has not been studied simultaneously. Since selective toxicity can change the size distribution of populations, we assumed that hormesis alters the size distribution at the population level, and investigated whether and how these two low-dose phenomena coexist. The study was conducted with Lactuca sativa L. exposed to the auxin-inhibitor 2-(p-chlorophenoxy)-2-methylpropionic acid (PCIB) in vitro. In two separate experiments, L. sativa was exposed to 12 PCIB doses in 24 replicates (50 plants/replicate). Shoot/root growth responses at the population level were compared to the fast-growing (≥90% percentile) and the slow-growing subpopulations (≤10% percentile) by Mann-Whitney U testing and dose-response modelling. In the formation of pronounced PCIB hormesis at the population level, low-dose effects proved selective, but widely stimulatory which seems to counteract low-dose selective toxicity. The selectivity of hormesis was dose- and growth rate-dependent. Stimulation occurred at lower concentrations and stimulation percentage was higher among slow-growing individuals, but partly or entirely masked at the population level by moderate or negligible stimulation among the faster growing individuals. We conclude that the hormetic effect up to the maximum stimulation may be primarily facilitated by an increase in size of the most slow-growing individuals, while thereafter it seems that mainly the fast-growing individuals contributed to the observed hormesis at the population level. As size distribution within a population is related to survival, our study hints that selective effects on slow

  8. Helicotylenchus stylocercus n. sp. and Rotylenchus phaliurus n. sp. (Nematoda: Hoplolaimidae) from Costa Rica.

    Science.gov (United States)

    Siddiqi, M R; Pinochet, J

    1979-10-01

    Two new species of plant-parasitic nematodes from Costa Rica are described. Helicotygenchus styloeercus n. sp., from soil around roots of banana at Coto, is distinguished hy the female tail, which bears a large pillarlike ventral projection. Rotylenchus phaliurus n. sp., from soil artmnd roots of Dioscoroea sp. at Sixaola, differs from R. caudaphasmidius in having the conus equal to or more than half the spear length, and large terminal annules on the female tail.

  9. SP (4,R) symmetry in light nuclei

    International Nuclear Information System (INIS)

    Peterson, D.R.

    1979-01-01

    A classification of nuclear states according to the noncompact sympletic Lie algebras sp(2n,R), n = 1, 2, 3, is investigated. Such a classification has recently been shown to be physically meaningful. This classification scheme is the appropriate generalization fo Elliott's SU 3 model of rotational states in deformed light nuclei to include core excitations. A restricted classification according to the Lie algebra, sp(4,R), is motivated. Truncation of the model space to a single sp(4,R) irreducible representation allows the inclusion of states possessing very high excitation energy. An sp(4,R) model study is performed on S = T = 0 positive-parity rotational bands in the deformed light nuclei 16 O and 24 Mg. States are included in the model space that possess up to 10h ω in excitation energy. Results for the B(E2) transition rates compare favorable with experiment, without resort to effective charges

  10. EOP Gold Coral (Gerardia sp.) Growth Measurements

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gold coral (Gerardia sp.) trees that were inspected years earlier on Pisces submersible dives were revisited and their change in size measured. The fishery for...

  11. Picarola margalefii, gen. et sp. nov., a new planktonic coccolithophore from NW Mediterranean waters

    Directory of Open Access Journals (Sweden)

    Lluïsa Cros

    2004-04-01

    Full Text Available A coccolithophore which is referred to a new genus Picarola gen. nov. and described as a new species Picarola margalefii sp. nov., has been observed from the NW Mediterranean. The description of the new species is based on Scanning Electronic Microscopy (SEM observations. The coccoliths of Picarola margalefii sp. nov. are muroliths that have a narrow high rim and a central area with a cross and an elongate four-sided central process. Energy dispersive X-ray microanalyses confirmed their calcareous nature. The relation between the new genus and the genera Papposphaera Tangen, Vexillarius Jordan et Chamberlain, and Turrilithus Jordan et al., is discussed. The coccolithophore Picarola margalefii gen. et sp. nov., is dedicated to Dr. Ramon Margalef.

  12. Silencing the SpMPK1, SpMPK2, and SpMPK3 Genes in Tomato Reduces Abscisic Acid—Mediated Drought Tolerance

    Directory of Open Access Journals (Sweden)

    Yan Liang

    2013-11-01

    Full Text Available Drought is a major threat to agriculture production worldwide. Mitogen-activated protein kinases (MAPKs play a pivotal role in sensing and converting stress signals into appropriate responses so that plants can adapt and survive. To examine the function of MAPKs in the drought tolerance of tomato plants, we silenced the SpMPK1, SpMPK2, and SpMPK3 genes in wild-type plants using the virus-induced gene silencing (VIGS method. The results indicate that silencing the individual genes or co-silencing SpMPK1, SpMPK2, and SpMPK3 reduced the drought tolerance of tomato plants by varying degrees. Co-silencing SpMPK1 and SpMPK2 impaired abscisic acid (ABA-induced and hydrogen peroxide (H2O2-induced stomatal closure and enhanced ABA-induced H2O2 production. Similar results were observed when silencing SpMPK3 alone, but not when SpMPK1 and SpMPK2 were individually silenced. These data suggest that the functions of SpMPK1 and SpMPK2 are redundant, and they overlap with that of SpMPK3 in drought stress signaling pathways. In addition, we found that SpMPK3 may regulate H2O2 levels by mediating the expression of CAT1. Hence, SpMPK1, SpMPK2, and SpMPK3 may play crucial roles in enhancing tomato plants’ drought tolerance by influencing stomatal activity and H2O2 production via the ABA-H2O2 pathway.

  13. Electron Microscopy.

    Science.gov (United States)

    Beer, Michael

    1980-01-01

    Reviews technical aspects of structure determination in biological electron microscopy (EM). Discusses low dose EM, low temperature microscopy, electron energy loss spectra, determination of mass or molecular weight, and EM of labeled systems. Cites 34 references. (CS)

  14. Electronic components

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Components provides a basic grounding in the practical aspects of using and selecting electronics components. The book describes the basic requirements needed to start practical work on electronic equipment, resistors and potentiometers, capacitance, and inductors and transformers. The text discusses semiconductor devices such as diodes, thyristors and triacs, transistors and heat sinks, logic and linear integrated circuits (I.C.s) and electromechanical devices. Common abbreviations applied to components are provided. Constructors and electronics engineers will find the book useful

  15. Understand electronics

    CERN Document Server

    Bishop, Owen

    2013-01-01

    Understand Electronics provides a readable introduction to the exciting world of electronics for the student or enthusiast with little previous knowledge. The subject is treated with the minimum of mathematics and the book is extensively illustrated.This is an essential guide for the newcomer to electronics, and replaces the author's best-selling Beginner's Guide to Electronics.The step-by-step approach makes this book ideal for introductory courses such as the Intermediate GNVQ.

  16. Vacuum electronics

    CERN Document Server

    Eichmeier, Joseph A

    2008-01-01

    Nineteen experts from the electronics industry, research institutes and universities have joined forces to prepare this book. ""Vacuum Electronics"" covers the electrophysical fundamentals, the present state of the art and applications, as well as the future prospects of microwave tubes and systems, optoelectronics vacuum devices, electron and ion beam devices, light and X-ray emitters, particle accelerators and vacuum interrupters. These topics are supplemented by useful information about the materials and technologies of vacuum electronics and vacuum technology.

  17. Electronic Commerce

    OpenAIRE

    Slavko Đerić

    2016-01-01

    Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks...

  18. Neutron induced electron radiography

    International Nuclear Information System (INIS)

    Andrade, Marcos Leandro Garcia

    2008-01-01

    In the present paper a new radiography technique, the 'Neutron Induced Electron Radiography' - NIER, to inspect low thickness samples on the order of micra, has been developed. This technique makes use of low energy electrons as penetrating radiation generated from metallic gadolinium screens when irradiated by thermal neutrons. The conditions to obtain the best image for the conventional X-ray film Kodak-AA were determined by using a digital system to quantify the darkening level of the film. The irradiations have been performed at a radiography equipment installed at the beam-hole no. 8 of the 5 MW IEA-R1 nuclear research reactor of IPEN-CNEN/SP. The irradiation time to obtain the best radiography was 100 seconds and for such condition the technique was able to discern 1 μm in 24 μm of aluminum at a resolution of 32 μm. By visual comparison the images obtained by the NIER shown a higher quality when compared with the ones from other usual techniques the make use of electrons a penetrating radiation and films for image registration. Furthermore the use of the digital system has provided a smaller time for data acquisition and data analysis as well as an improvement in the image visualization. (author)

  19. Copper and Cadmium Toxicity to Marine Phytoplankton, Chaetoceros gracilis and Isochrysis sp.

    Directory of Open Access Journals (Sweden)

    Suratno Suratno

    2015-07-01

    Full Text Available In Copper (Cu based antifouling (AF paints Cu was largely used as booster biocide after organotin was banned. Cu is micronutrient which is important in photosynthesis process because Cu is an essential metal as component of enzyme and electron transport chain. But in certain dosage, Cu could be toxic to marine organism. Chaetoceros gracilis and Isochrysis sp. are dominant microalgae in aquatic ecosystem. In this study the effect of Cu and Cadmium (Cd on two marine microalgae, C. gracilis and Isochrysis sp. were compared. Toxicity test was based on American Standard for Testing Material (ASTM. IC50-96 h of Cd as reference toxicant was 2,370 mg.L-1 for C. gracilis and 490 mg.L-1 for Isochrysis sp. IC50-96 h of Cu to growth of C. gracilis was 63.75 mg.L-1 and Isochrysis sp. was 31.80 mg.L-1. Both Cd and Cu were inhibited growth of microalgae. Based on IC50-96 h value, it could be concluded that Cu was more toxic than Cd. Toxicity of Cu was 37 times stronger than Cd for C. gracilis and 15 times for Isochrysis sp. It was estimated that at concentration 10 mg.L-1 Cu does not show observable effect (NOEC to C. gracilis and 5 mg.L-1 to Isochrysis sp. The lowest observable effect of Cu (LOEC to C. gracilis was at concentration 17 mg.L-1 and 10 mg.L-1 for Isochrysis sp.

  20. Electronic Publishing.

    Science.gov (United States)

    Lancaster, F. W.

    1989-01-01

    Describes various stages involved in the applications of electronic media to the publishing industry. Highlights include computer typesetting, or photocomposition; machine-readable databases; the distribution of publications in electronic form; computer conferencing and electronic mail; collaborative authorship; hypertext; hypermedia publications;…

  1. ELECTRONIC SIGNATURES

    African Journals Online (AJOL)

    10332324

    (a) facilitate ecommerce;2. (b) remove and prevent barriers to electronic communications in South Africa;3. (c) ensure that electronic transactions in the Republic conform to the highest international standards;4. (d) promote the development of electronic transactions services which are responsive to the needs of users and ...

  2. Biochemical basis of mercury remediation and bioaccumulation by Enterobacter sp. EMB21.

    Science.gov (United States)

    Sinha, Arvind; Kumar, Sumit; Khare, Sunil Kumar

    2013-01-01

    The aims of this study were to isolate metal bioaccumulating bacterial strains and to study their applications in removal of environmental problematic heavy metals like mercury. Five bacterial strains belonging to genera Enterobacter, Bacillus, and Pseudomonas were isolated from oil-spilled soil. Among these, one of the strains Enterobacter sp. EMB21 showed mercury bioaccumulation inside the cells simultaneous to its bioremediation. The bioaccumulation of remediated mercury was confirmed by transmission electron microscopy and energy dispersive X-ray. The mercury-resistant loci in the Enterobacter sp. EMB21 cells were plasmid-mediated as confirmed by transformation of mercury-sensitive Escherichia coli DH5α by Enterobacter sp. EMB21 plasmid. Effect of different culture parameters viz-a-viz inoculum size, pH, carbon, and nitrogen source revealed that alkaline pH and presence of dextrose and yeast extract favored better remediation. The results indicated the usefulness of Enterobacter sp. EMB21 for the effective remediation of mercury in bioaccumulated form. The Enterobacter sp. EMB21 seems promising for heavy metal remediation wherein the remediated metal can be trapped inside the cells. The process can further be developed for the synthesis of valuable high-end functional alloy, nanoparticles, or metal conjugates from the metal being remediated.

  3. Basic electronics

    CERN Document Server

    Holbrook, Harold D

    1971-01-01

    Basic Electronics is an elementary text designed for basic instruction in electricity and electronics. It gives emphasis on electronic emission and the vacuum tube and shows transistor circuits in parallel with electron tube circuits. This book also demonstrates how the transistor merely replaces the tube, with proper change of circuit constants as required. Many problems are presented at the end of each chapter. This book is comprised of 17 chapters and opens with an overview of electron theory, followed by a discussion on resistance, inductance, and capacitance, along with their effects on t

  4. Sticker electronics

    KAUST Repository

    Hussain, Muhammad Mustafa

    2017-09-08

    Electronic stickers may be manufactured on flexible substrates (110, 120, 130) as layers and packaged together. The package may then have an adhesive applied to one side to provide capability for sticking the electronic devices to surfaces. The stickers can be wrappable, placed on surfaces, glued on walls or mirrors or wood or stone, and have electronics (112, 122, 132) which may or may not be ultrathin. Packaging for the electronic sticker can use polymer on cellulose manufacturing and/or three dimensional (3-D) printing. The electronic stickers may provide lighting capability, sensing capability, and/or recharging capabilities.

  5. Low-energy electron irradiation induced top-surface nanocrystallization of amorphous carbon film

    Science.gov (United States)

    Chen, Cheng; Fan, Xue; Diao, Dongfeng

    2016-10-01

    We report a low-energy electron irradiation method to nanocrystallize the top-surface of amorphous carbon film in electron cyclotron resonance plasma system. The nanostructure evolution of the carbon film as a function of electron irradiation density and time was examined by transmission electron microscope (TEM) and Raman spectroscopy. The results showed that the electron irradiation gave rise to the formation of sp2 nanocrystallites in the film top-surface within 4 nm thickness. The formation of sp2 nanocrystallite was ascribed to the inelastic electron scattering in the top-surface of carbon film. The frictional property of low-energy electron irradiated film was measured by a pin-on-disk tribometer. The sp2 nanocrystallized top-surface induced a lower friction coefficient than that of the original pure amorphous film. This method enables a convenient nanocrystallization of amorphous surface.

  6. Penggunaan Jamur Antagonis Trichoderma SP. Dan Gliocladium SP. Untuk Mengendalikan Penyakit Layu Fusarium Pada Tanaman Bawang Merah (Allium Ascalonicum L.)

    OpenAIRE

    Arie Ramadhina, Arie Ramadhina; Lisnawita, Lisnawita; Lubis, Lahmuddin

    2013-01-01

    The use of antagonism fungus of Trichoderma sp. and Gliocladium sp. for controlling wilt(Fusarium oxysporum) in red onion plants. The aim of the research was to know the effectiviness ofantagonism fungus of Trichoderma sp. and Gliocladium sp. in controlling wilt in red onion plants.The research used non-factorial RAK (random group design) with eight treatments: control, 10grams of F. oxysporum, 12 grams of Trichoderma sp., 18 grams of Trichoderma sp., 24 grams ofTrichoderma sp., and 12 grams ...

  7. Electron Tree

    DEFF Research Database (Denmark)

    Appelt, Ane L; Rønde, Heidi S

    2013-01-01

    The photo shows a close-up of a Lichtenberg figure – popularly called an “electron tree” – produced in a cylinder of polymethyl methacrylate (PMMA). Electron trees are created by irradiating a suitable insulating material, in this case PMMA, with an intense high energy electron beam. Upon discharge......, during dielectric breakdown in the material, the electrons generate branching chains of fractures on leaving the PMMA, producing the tree pattern seen. To be able to create electron trees with a clinical linear accelerator, one needs to access the primary electron beam used for photon treatments. We...... appropriated a linac that was being decommissioned in our department and dismantled the head to circumvent the target and ion chambers. This is one of 24 electron trees produced before we had to stop the fun and allow the rest of the accelerator to be disassembled....

  8. The electron and the electronics

    International Nuclear Information System (INIS)

    Sanchez Balmaseda, M.

    1997-01-01

    The aim of this work is to present a brief report of those historical events that originated and contributed to the scientific area of Electronics. The main discovering and investigations in both Vacuum Electronics and Semiconductor Electronics are reviewed. (Author) 12 refs

  9. Chaenorhinum semispeluncarum sp. nov. and C. yildirimlii sp. nov. (Scrophulariaceae) from east Anatolia, Turkey

    DEFF Research Database (Denmark)

    Yildirim, Hasan; Tan, Kit; Senol, Serdar

    2010-01-01

    Chaenorhinum semispeluncarum H. Yildirim, Kit Tan, S. Senol & A. Pirhan sp. nov. and C. yildirimlii Kit Tan, H. Yildirim, S. Senol & A. Pirhan sp. nov. (Scrophulariaceae, C. sect. Microrrhinum) from east Anatolia are described and illustrated. They are both narrow endemics related to the rare C...

  10. Two new species of nematode parasites, Cucullanus epinepheli sp. n. (Cucullanidae) and Procamallanus (Spirocamallanus) sinespinis sp. n. (Camallanidae), from marine serranid and haemulid fishes off New Caledonia.

    Science.gov (United States)

    Moravec, Frantisek; Justine, Jean-Lou

    2017-04-05

    Based on light and scanning electron microscopical studies, two new species of parasitic nematodes are described from marine perciform fishes off New Caledonia: Cucullanus epinepheli sp. n. (Cucullanidae) from the intestine of the brownspotted grouper Epinephelus chlorostigma (Valenciennes) (Serranidae) and Procamallanus (Spirocamallanus) sinespinis sp. n. from the intestine of the silver grunt Pomadasys argenteus (Forsskål) (Haemulidae). Cucullanus epinepheli sp. n. differs from its congeners mainly in possessing a unique structure of the anterior, elevated cloacal lip with a large posterior outgrowth covering the cloacal aperture and in the presence of cervical alae and two small preanal papillae on the median dome-shaped precloacal elevation. This is the second known nominal species of this genus parasitising fishes of the family Serranidae and the second representative of Cucullanus Müller, 1777 recorded from fishes in New Caledonian waters. Procamallanus (Spirocamallanus) sinespinis sp. n. is mainly characterised by 10-12 spiral ridges in the buccal capsule, the presence of wide caudal alae, three pairs of pedunculate preanal papillae, two unequally long spicules (465-525 µm and 218-231 µm) and by the tail tip with a knob-like structure in the male, and the broad, rounded tail with a terminal digit-like protrusion without cuticular spikes in the female. This is the fifth nominal species of the subgenus Spirocamallanus Olsen, 1952 reported from fishes in New Caledonian waters.

  11. sp3-Bonded silicon allotropes based on the Kelvin problem.

    Science.gov (United States)

    Zhao, Hui-Yan; Wang, Jing; Ma, Qing-Min; Liu, Ying

    2013-10-28

    The Kelvin problem, how to partition three-dimensional space into cells of equal volume with minimal area, is a fascinating one. Aggregations of bubbles are naturally physical illustrations of the Kelvin problem. And the superconductor Na8Si46 as an inspiration leads to an amazing discovery of the Weaire-Phelan (WP) structure of foam - the optimal solution to the Kelvin problem to date. Here based on the structural similarity between sp(3)-bonded silicon allotropes and the solutions to the Kelvin problem, a series of new sp(3)-hybridization silicon allotropes, named "Kelvin Silicons", are presented. Furthermore, the structural stability and electronic properties of these new silicon allotropes are investigated using density-functional theory (DFT) calculations. The results show that Kelvin Silicons are structurally stable semiconductors with indirect bandgaps in the range of 0.17-1.40 eV, and their bulk moduli are about 75.9-88.5% that of the diamond phase. The simulated X-ray diffraction spectra of the new silicon crystalline structures would provide more information for possible experimental observations and synthesis.

  12. Enhancement of electricity production in a mediatorless air-cathode microbial fuel cell using Klebsiella sp. IR21.

    Science.gov (United States)

    Lee, Yun-Yeong; Kim, Tae Gwan; Cho, Kyung-Suk

    2016-06-01

    A novel dissimilatory iron-reducing bacteria, Klebsiella sp. IR21, was isolated from the anode biofilm of an MFC reactor. Klebsiella sp. IR21 reduced 27.8 % of ferric iron to ferrous iron demonstrating that Klebsiella sp. IR21 has electron transfer ability. Additionally, Klebsiella sp. IR21 generated electricity forming a biofilm on the anode surface. When a pure culture of Klebsiella sp. IR21 was supplied into a single chamber, air-cathode MFC fed with a mixture of glucose and acetate (500 mg L(-1) COD), 40-60 mV of voltage (17-26 mA m(-2) of current density) was produced. Klebsiella sp. IR21 was also utilized as a biocatalyst to improve the electrical performance of a conventional MFC reactor. A single chamber, air-cathode MFC was fed with reject wastewater (10,000 mg L(-1) COD) from a H2 fermentation reactor. The average voltage, current density, and power density were 142.9 ± 25.74 mV, 60.5 ± 11.61 mA m(-2), and 8.9 ± 3.65 mW m(-2), respectively, in the MFC without inoculation of Klebsiella sp. IR21. However, these electrical performances of the MFC were significantly increased to 204.7 ± 40.24 mV, 87.5 ± 17.20 mA m(-2), and 18.6 ± 7.23 mW m(-2), respectively, with inoculation of Klebsiella sp. IR21. The results indicate that Klebsiella sp. IR21 can be utilized as a biocatalyst for enhancement of electrical performance in MFC systems.

  13. Di-and tri-hydroxylated Kaurane derivatives from microbial transformation of Ent-Kaur-16-En-19-Ol by Cephalosporium aphidicola and their allelopathic activity on Lactuca sativa (lettuce)

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, D.; Takahashi, J.A.; Boaventura, M.A.D. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Quimica], e-mail: dianadb@netuno.lcc.ufmg.br

    2009-01-15

    The use of microorganisms to induce chemical modifications in organic molecules is a very useful tool in organic synthesis, to obtain biologically active substances. The fungus Cephalosporium aphidicola is known by its ability to hydroxylate several skeleton positions of many classes of organic compounds. In this work, the microbial transformation of ent-kaur-16-en-19-01 (1) by C. aphidicola, afforded two hydroxylated compounds, ent-kauran-16{beta},19-diol (2) and ent-kauran-16{beta},17,19-triol (3). Their structures were established by 1D and 2D-NMR studies. Both compounds were tested for their action on the growth of radical and shoot of Lactuca sativa. (author)

  14. Metallaphotoredox-catalysed sp3-sp3 cross-coupling of carboxylic acids with alkyl halides

    Science.gov (United States)

    Johnston, Craig P.; Smith, Russell T.; Allmendinger, Simon; MacMillan, David W. C.

    2016-08-01

    In the past 50 years, cross-coupling reactions mediated by transition metals have changed the way in which complex organic molecules are synthesized. The predictable and chemoselective nature of these transformations has led to their widespread adoption across many areas of chemical research. However, the construction of a bond between two sp3-hybridized carbon atoms, a fundamental unit of organic chemistry, remains an important yet elusive objective for engineering cross-coupling reactions. In comparison to related procedures with sp2-hybridized species, the development of methods for sp3-sp3 bond formation via transition metal catalysis has been hampered historically by deleterious side-reactions, such as β-hydride elimination with palladium catalysis or the reluctance of alkyl halides to undergo oxidative addition. To address this issue, nickel-catalysed cross-coupling processes can be used to form sp3-sp3 bonds that utilize organometallic nucleophiles and alkyl electrophiles. In particular, the coupling of alkyl halides with pre-generated organozinc, Grignard and organoborane species has been used to furnish diverse molecular structures. However, the manipulations required to produce these activated structures is inefficient, leading to poor step- and atom-economies. Moreover, the operational difficulties associated with making and using these reactive coupling partners, and preserving them through a synthetic sequence, has hindered their widespread adoption. A generically useful sp3-sp3 coupling technology that uses bench-stable, native organic functional groups, without the need for pre-functionalization or substrate derivatization, would therefore be valuable. Here we demonstrate that the synergistic merger of photoredox and nickel catalysis enables the direct formation of sp3-sp3 bonds using only simple carboxylic acids and alkyl halides as the nucleophilic and electrophilic coupling partners, respectively. This metallaphotoredox protocol is suitable for

  15. Preparation of miniantibodies to Azospirillum brasilense Sp245 surface antigens and their use for bacterial detection.

    Science.gov (United States)

    Dykman, Lev A; Staroverov, Sergei A; Guliy, Olga I; Ignatov, Oleg V; Fomin, Alexander S; Vidyasheva, Irina V; Karavaeva, Olga A; Bunin, Viktor D; Burygin, Gennady L

    2012-01-01

    This article reports the first preparation of miniantibodies to Azospirillum brasilense Sp245 surface antigens by using a combinatorial phage library of sheep antibodies. The prepared phage antibodies were used for the first time for lipopolysaccharide and flagellin detection by dot assay, electro-optical analysis of cell suspensions, and transmission electron microscopy. Interaction of A. brasilense Sp245 with antilipopolysaccharide and antiflagellin phage-displayed miniantibodies caused the magnitude of the electro-optical signal to change considerably. The electro-optical results were in good agreement with the electron microscopic data. This is the first reported possibility of employing phage-displayed miniantibodies in bacterial detection aided by electro-optical analysis of cell suspensions.

  16. Seasonal variation in an annually-banded coral Porites: A scanning electron microscopy investigation

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.A.S.

    Seasonal bands of the hard coral @iPorites@@ sp. collected from three different islands of Lakshadweep (Northwest Indian Ocean) are examined under a scanning electron microscope (SEM). SEM photographs reveal the presence of detrital inclusions...

  17. Electronic Commerce

    Directory of Open Access Journals (Sweden)

    Slavko Đerić

    2016-12-01

    Full Text Available Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks, including the Internet. Electronic commerce is not limited just to buying and selling, but it also includes all pre-sales and after-sales ongoing activities along the supply chain. Introducing electronic commerce, using the Internet and Web services in business, realizes the way to a completely new type of economy - internet economy.

  18. Graphene-on-diamond devices with increased current-carrying capacity: carbon sp2-on-sp3 technology.

    Science.gov (United States)

    Yu, Jie; Liu, Guanxiong; Sumant, Anirudha V; Goyal, Vivek; Balandin, Alexander A

    2012-03-14

    Graphene demonstrated potential for practical applications owing to its excellent electronic and thermal properties. Typical graphene field-effect transistors and interconnects built on conventional SiO(2)/Si substrates reveal the breakdown current density on the order of 1 μA/nm(2) (i.e., 10(8) A/cm(2)), which is ~100× larger than the fundamental limit for the metals but still smaller than the maximum achieved in carbon nanotubes. We show that by replacing SiO(2) with synthetic diamond, one can substantially increase the current-carrying capacity of graphene to as high as ~18 μA/nm(2) even at ambient conditions. Our results indicate that graphene's current-induced breakdown is thermally activated. We also found that the current carrying capacity of graphene can be improved not only on the single-crystal diamond substrates but also on an inexpensive ultrananocrystalline diamond, which can be produced in a process compatible with a conventional Si technology. The latter was attributed to the decreased thermal resistance of the ultrananocrystalline diamond layer at elevated temperatures. The obtained results are important for graphene's applications in high-frequency transistors, interconnects, and transparent electrodes and can lead to the new planar sp(2)-on-sp(3) carbon-on-carbon technology. © 2012 American Chemical Society

  19. Antimicrobial metabolites from the plant endophytic fungus Penicillium sp.

    Science.gov (United States)

    Yang, Ming-Hua; Li, Tian-Xiao; Wang, Ying; Liu, Rui-Huan; Luo, Jun; Kong, Ling-Yi

    2017-01-01

    Five rare dichloro aromatic polyketides (1-5) were obtained from an endophytic fungus Penicillium sp., along with five known metabolites (6-10). Their structures were elucidated by extensive spectroscopic analysis, Mosher methods, as well as [Rh 2 (OCOCF 3 ) 4 ]-induced electronic circular dichroism (ECD) experiments. Compounds 2-4 and 6 structurally involved acyclic 1.3-diols, the uneasy configuration determinations of which were well carried out by double-derivation NMR methods. Compounds 1-10 were evaluated for their antibacterial and antifungal activities against five strains of human pathogenic microorganisms. Helvolic acid (7) showed potent inhibitory effects against Staphylococcus aureus and Pseudomonas aeruginosa with MIC (minimum inhibitory concentration) values of 5.8 and 4.6μg/mL, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Bioremediation potential, growth and biomass yield of the green seaweed, Ulva lactuca in an integrated marine aquaculture system at the Red Sea coast of Saudi Arabia at different stocking densities and effluent flow rates

    KAUST Repository

    Al-Hafedh, Yousef S.

    2014-03-19

    Growth, production and biofiltration rates of seaweed, Ulva lactuca were investigated at two stocking densities (3 kg and 6 kg m-2) and two effluent flow rates (5.4 and 10.8 m3 day-1) to optimize an integrated mariculture system at Saudi Red Sea coast. effluents from fish-rearing tank, stocked with 200 kg fish (Oreochromis spilurus), fed to six seaweed tanks via sedimentation tank. Fish growth (weight gain 1.75 g fish day-1), net production (NP, 10.16 kg m-3) and survival (94.24%) were within acceptable limits. Ulva showed significantly higher (F = 62.62, d.f. 3, 35; P < 0.0001) specific growth rates at lower density compared with higher density and under high flow versus low flow (SGR = 5.78% vs. 2.55% at lower flow and 10.60% vs. 6.26% at higher flow). Biomass yield of Ulva at low- and high-stocking densities (111.11 and 83.2 g wet wt m-2 day-1, respectively) at low flow and (267.44 and 244.19 g wet wt m-2 day-1, respectively) at high flow show that high flow rate and lower density favoured growth. Removal rates of total ammonia nitrogen (TAN) (0.26-0.31 g m-2 day-1) and phosphate phosphorus (0.32-0.41 g m-2 day-1) by U. lactuca were not significantly different (F = 1.9, d.f. 3, 59; P = 0.1394 for TAN and F = 0.29, d.f. 3, 59; P = 0.8324 for phosphates) at both the flow rates and stocking densities. Results show that the effluent flow rate has significant impact over the performance of the seaweed than stocking density.

  1. Five novel Wickerhamomyces- and Metschnikowia-related yeast species, Wickerhamomyces chaumierensis sp. nov., Candida pseudoflosculorum sp. nov., Candida danieliae sp. nov., Candida robnettiae sp. nov. and Candida eppingiae sp. nov., isolated from plants

    NARCIS (Netherlands)

    Groenewald, Marizeth; Robert, Vincent; Smith, Maudy Th

    On the basis of nucleotide divergences in the D1/D2 domain of the 26S rRNA gene and the internal transcribed spacers (ITS) domain of the rRNA gene, five novel yeast species, Wickerhamomyces chaumierensis sp. nov. (CBS 8565(T)  = JCM 17246(T)), Candida pseudoflosculorum sp. nov. (CBS 8584(T)  = JCM

  2. Electron spectroscopy

    International Nuclear Information System (INIS)

    Hegde, M.S.

    1979-01-01

    An introduction to the various techniques in electron spectroscopy is presented. These techniques include: (1) UV Photoelectron spectroscopy, (2) X-ray Photoelectron spectroscopy, (3) Auger electron spectroscopy, (4) Electron energy loss spectroscopy, (5) Penning ionization spectroscopy and (6) Ion neutralization spectroscopy. The radiations used in each technique, the basis of the technique and the special information obtained in structure determination in atoms and molecules by each technique are summarised. (A.K.)

  3. Polymer electronics

    CERN Document Server

    Hsin-Fei, Meng

    2013-01-01

    Polymer semiconductor is the only semiconductor that can be processed in solution. Electronics made by these flexible materials have many advantages such as large-area solution process, low cost, and high performance. Researchers and companies are increasingly dedicating time and money in polymer electronics. This book focuses on the fundamental materials and device physics of polymer electronics. It describes polymer light-emitting diodes, polymer field-effect transistors, organic vertical transistors, polymer solar cells, and many applications based on polymer electronics. The book also disc

  4. Electron Bifurcation

    Energy Technology Data Exchange (ETDEWEB)

    Peters, John W.; Miller, Anne-Frances; Jones, Anne K.; King, Paul W.; Adams, Michael W. W.

    2016-04-01

    Electron bifurcation is the recently recognized third mechanism of biological energy conservation. It simultaneously couples exergonic and endergonic oxidation-reduction reactions to circumvent thermodynamic barriers and minimize free energy loss. Little is known about the details of how electron bifurcating enzymes function, but specifics are beginning to emerge for several bifurcating enzymes. To date, those characterized contain a collection of redox cofactors including flavins and iron-sulfur clusters. Here we discuss the current understanding of bifurcating enzymes and the mechanistic features required to reversibly partition multiple electrons from a single redox site into exergonic and endergonic electron transfer paths.

  5. Microfluidic electronics.

    Science.gov (United States)

    Cheng, Shi; Wu, Zhigang

    2012-08-21

    Microfluidics, a field that has been well-established for several decades, has seen extensive applications in the areas of biology, chemistry, and medicine. However, it might be very hard to imagine how such soft microfluidic devices would be used in other areas, such as electronics, in which stiff, solid metals, insulators, and semiconductors have previously dominated. Very recently, things have radically changed. Taking advantage of native properties of microfluidics, advances in microfluidics-based electronics have shown great potential in numerous new appealing applications, e.g. bio-inspired devices, body-worn healthcare and medical sensing systems, and ergonomic units, in which conventional rigid, bulky electronics are facing insurmountable obstacles to fulfil the demand on comfortable user experience. Not only would the birth of microfluidic electronics contribute to both the microfluidics and electronics fields, but it may also shape the future of our daily life. Nevertheless, microfluidic electronics are still at a very early stage, and significant efforts in research and development are needed to advance this emerging field. The intention of this article is to review recent research outcomes in the field of microfluidic electronics, and address current technical challenges and issues. The outlook of future development in microfluidic electronic devices and systems, as well as new fabrication techniques, is also discussed. Moreover, the authors would like to inspire both the microfluidics and electronics communities to further exploit this newly-established field.

  6. Electronics Industry

    National Research Council Canada - National Science Library

    Bell, Robert; Carroll-Garrison, Martina; Donovan, Daniel; Fisher, John; Guemmer, Paul; Harms, Robert; Kelly, Timothy; Love, Mattie; McReynolds, James; Ward, Ralph

    2006-01-01

    .... Government action to preserve strategic access to semiconductor producers is clearly needed to ensure DoD electronic systems can be built without compromising sensitive technology, though every...

  7. Isolated electrons

    Energy Technology Data Exchange (ETDEWEB)

    Ekstrom, Ph.; Winwland, D.

    1981-08-01

    The problem of electron g-factor measurement by means of an isolated electron is considered. The technique of the experiment performed at the Washington university is described. A single electron is enclosed in a homogeneous magnetic field which is superimposed by an electric field. The electric field configuration represents a Penning trap. The trap together with the enclosed electron forms an ''atom'' of macroscopic dimensions. The electron trajectory in the trap consists of three components. The electron quickly rotates over small loops (cyclotron motion), the centre of these loops slowly moves over a large circle (magistron motion). Meanwhile the electron oscillates back and forth along the trap axis. The electron motion in the atom field is quantized and the transitions between various types of motions correspond to definite radiation frequencies. At the anomal frequency the transition with spin flip is registered and the electron g-factor is measured. The value g=2.0023193044 is obtained with a probable error less than a unit of the last decimal digit.

  8. The influence of the combined effects of acute gamma-radiation, sodium bromate and sodium nitrate on lettuce (Lactuca sativa) seedling root growth

    Energy Technology Data Exchange (ETDEWEB)

    Pryakhin, E.; Osipov, D. [Urals Research Center for Radiation Medicine - URCRM (Russian Federation)

    2014-07-01

    Among special industrial reservoirs used for the storage of liquid radioactive waste of Mayak PA, Russia, one of the most radioactively contaminated is the R-17 reservoir, so-called 'Staroye Boloto' (the total β-activity of water ranged in the observation period from 0.4 MBq/l to 4.5 MBq/l, the total a-activity ranged from 43 to 420 Bq/l). Also this reservoir is characterized by high level of chemical contamination, in particular, the concentration of nitrates in water is 2.5-4,4 g/l, sodium bromate - up to 35 mg/l. One of the interesting questions is interaction of radiation and chemical contamination in their effect on living organisms in this reservoir. In laboratory experiments seeds of Lactuca sativa were used; the effect of the studied factor on the length of the sprout's root was estimated. To assess the effect of chemical toxicants the solutions of each salt in 7 different concentrations were used, distilled water was used as a control. For evaluation of acute effects of external gamma irradiation the seeds after exposure for 24 hours in distilled water, were irradiated at 7 different doses using gamma-unit on the basis of Cs-137 with the dose rate of 0.62 Gy/min. To assess the combined effects of acute external gamma irradiation, of nitrates and bromates, seeds after 24 hour exposure at each test concentration of the salts solutions were irradiated using gamma-unit. To calculate the effective concentrations or doses was used drc package for R software. To calculate the dose rate to aquatic organisms in the R-17 was used ERICA Assessment Tool 2012. It was found out that the EC50 of sodium nitrate for lettuce was 2.69 g/l, which is comparable to the concentration of nitrates in the 'Staroye Boloto'. This indicates that nitrate can have significant toxic effect on aquatic higher plants of the reservoir. The EC50 of sodium bromate was 14.6 mg/l. This is less than the maximum concentration of the substance in the R-17, which suggests

  9. SP-100/Brayton power system concepts

    International Nuclear Information System (INIS)

    Owen, D.F.

    1989-01-01

    Use of closed Brayton cycle (CBC) power conversion technology has been investigated for use with SP-100 reactors for space power systems. The CBC power conversion technology is being developed by Rockwell International under the Dynamic Isotype Power System (DIPS) and Space Station Freedom solar dynamic power system programs to provide highly efficient power conversion with radioisotype and solar collector heat sources. Characteristics including mass, radiator area, thermal power, and operating temperatures for systems utilizing SP-100 reactor and CBC power conversion technology were determined for systems in the 10-to 100-kWe power range. Possible SP-100 reactor/CBC power system configurations are presented. Advantages of CBC power conversion technology with regard to reactor thermal power, operating temperature, and development status are discussed

  10. Co-Catalyzed Direct Addition of Allylic C(sp3)-H Bonds to Ketones.

    Science.gov (United States)

    Mita, Tsuyoshi; Hanagata, Satoshi; Michigami, Kenichi; Sato, Yoshihiro

    2017-11-03

    By using Co(acac) 2 /Xantphos with AlMe 3 , the C(sp 3 )-H bonds of allylarene derivatives were cleaved for reaction with various ketones, affording the homoallylic alcohols in moderate to good yields. The branch/linear selectivity depended on the steric and electronic factors of the ketone electrophiles. The intermediate in this reaction is thought to be a low-valent allylcobalt(I) species, which exhibits high nucleophilicity toward ketones.

  11. The electron

    International Nuclear Information System (INIS)

    Hestenes, David; Weingartshofer, Antonio

    1991-01-01

    The stupendous successes of the Dirac equation and quantum electro-dynamics have established the electron as the best understood of the fundamental constituents of matter. Nevertheless, physicists agree that the electron still has secrets to reveal. Moreover, powerful new theoretical and experimental tools for probing those secrets have been sharpened during the last decade. This workshop was organized to bring theorists and experimentalists together to discuss their common goal of knowing the electron. Present state and future prospects for progress toward that goal are here described. The theoretical papers encompass a wide range of views on the electron. Several argue that the 'Zitter-bewegung' is more than a mathematical peculiarity of the Dirac equation, that it may well be a real physical phenomenon and worthy of serious study, theoretically and experimentally. Besides generating the electron spin and magnetic moment, the 'Zitterbewegung' may be a vital clue to electron structure and self-interaction. Some of the papers employ a radical new formulation of the Dirac theory which reveals a hidden geo-metric structure in the theory that supports a 'Zitterbewegung' inter-pretation. For the last half century the properties of electrons have been probed primarily by scattering experiments at ever higher energies. Recently, however, two powerful new experimental techniques have emerged capable of giving alternative experimental views of the electron. First, techniques for confining single electrons for long term study have led to the most accurate measurements of the electron magnetic moment. Second, the interaction of high intensity laser fields with atoms and electrons have revealed striking new phenomena such as multiphoton ionization. refs.; figs.; tabs

  12. Electronic marketplaces

    OpenAIRE

    TALAFOUSOVÁ, Jana

    2011-01-01

    This thesis describes the principles of electronic and Internet marketplaces. For analyzing the status of the use of electronic marketplaces and online polling was done with the actual marketplace and society, which is a member of the marketplace. Proposal that trade through the market is prepared for a particular company, which previously traded through the marketplace.

  13. Printed Electronics

    Science.gov (United States)

    Crain, John M. (Inventor); Lettow, John S. (Inventor); Aksay, Ilhan A. (Inventor); Korkut, Sibel (Inventor); Chiang, Katherine S. (Inventor); Chen, Chuan-Hua (Inventor); Prud'Homme, Robert K. (Inventor)

    2016-01-01

    Printed electronic device comprising a substrate onto at least one surface of which has been applied a layer of an electrically conductive ink comprising functionalized graphene sheets and at least one binder. A method of preparing printed electronic devices is further disclosed.

  14. Power electronics

    Indian Academy of Sciences (India)

    Kishore Chatterjee

    reference material for power electronics engineers, students and academicians. We thank the editors of Sadhana for inviting us to guest-edit this special issue on power electronics. July 2017. KISHORE CHATTERJEE. Department of Electrical Engineering,. Indian Institute of Technology,. Bombay, Powai, Mumbai 400076, ...

  15. Defluviimonas denitrificans gen. nov., sp. nov., and Pararhodobacter aggregans gen. nov., sp. nov., non-phototrophic Rhodobacteraceae from the biofilter of a marine aquaculture

    DEFF Research Database (Denmark)

    Foesel, Bärbel U.; Drake, Harold L.; Schramm, Andreas

    2011-01-01

    Three Gram-negative bacterial strains were isolated from the biofilter of a recirculating marine aquaculture. They were non-pigmented rods, mesophiles, moderately halophilic, and showed chemoorganoheterotrophic growth on various sugars, fatty acids, and amino acids, with oxygen as electron acceptor......, but clearly separate from, the genera Rhodobacter, Rhodovulum, and Rhodobaca. Based on morphological, physiological, and 16S rRNA-based phylogenetic characteristics, the isolated strains are proposed as new species of two novel genera, Defluviimonas denitrificans gen. nov., sp. nov. (type strain D9-3T = DSM...... 18921T = ATCC BAA-1447T; additional strain D11-58 = DSM19039 = ATCC BAA-1448) and Pararhodobacter aggregans gen. nov., sp. nov (type strain D1-19T = DSM 18938T = ATCC BAA-1446T)....

  16. Iron-catalyzed oxidative sp3carbon-hydrogen bond functionalization of 3,4-dihydro-1,4-benzoxazin-2-ones.

    Science.gov (United States)

    Huo, Congde; Dong, Jie; Su, Yingpeng; Tang, Jing; Chen, Fengjuan

    2016-11-08

    A novel and efficient iron-catalyzed sp 3 carbon-hydrogen bond functionalization of benzoxazinone derivatives has been developed. For the first time, benzoxazin-2-ones were used as substrates in an oxidative dehydrogenative coupling reaction. The experiments were performed under mild reaction conditions to construct alkyl-aryl C(sp 3 )-C(sp 2 ) bonds. The application of this method to the gram-scale synthesis of natural product cephalandole A has been accomplished in a 3-step sequence. A plausible one electron oxidation involved mechanism is proposed.

  17. Exogenous electron shuttle-mediated extracellular electron transfer of Shewanella putrefaciens 200: electrochemical parameters and thermodynamics.

    Science.gov (United States)

    Wu, Yundang; Liu, Tongxu; Li, Xiaomin; Li, Fangbai

    2014-08-19

    Despite the importance of exogenous electron shuttles (ESs) in extracellular electron transfer (EET), a lack of understanding of the key properties of ESs is a concern given their different influences on EET processes. Here, the ES-mediated EET capacity of Shewanella putrefaciens 200 (SP200) was evaluated by examining the electricity generated in a microbial fuel cell. The results indicated that all the ESs substantially accelerated the current generation compared to only SP200. The current and polarization parameters were linearly correlated with both the standard redox potential (E(ES)(0)) and the electron accepting capacity (EAC) of the ESs. A thermodynamic analysis of the electron transfer from the electron donor to the electrode suggested that the EET from c-type cytochromes (c-Cyts) to ESs is a crucial step causing the differences in EET capacities among various ESs. Based on the derived equations, both E(ES)(0) and EAC can quantitatively determine potential losses (ΔE) that reflect the potential loss of the ES-mediated EET. In situ spectral kinetic analysis of ES reduction by c-Cyts in a living SP200 suspension was first investigated with the E(ES), E(c-Cyt), and ΔE values being calculated. This study can provide a comprehensive understanding of the role of ESs in EET.

  18. Ovos de Toxocara sp. e larvas de Ancylostoma sp. em praça pública de Lavras, MG Toxocara sp. eggs and Ancylostoma sp. larva in public parks, Brazil

    Directory of Open Access Journals (Sweden)

    Antônio Marcos Guimarães

    2005-04-01

    Full Text Available Larva migrans visceral e cutânea são zoonoses parasitárias causadas pela infecção da larva de Toxocara sp. e Ancylostoma sp., respectivamente. O objetivo do estudo foi verificar a contaminação por ovos de Toxocara sp. e ovos e larvas de Ancylostoma sp. em amostras de solos coletadas de praças públicas e de áreas de recreação infantil de Lavras, Estado de Minas Gerais, por meio da técnica de centrífugo-flutuação e do método de Baermann. A ocorrência de ovos de Toxocara sp. e, ovos e larvas de Ancylostoma sp. foi observada em 69,6% (16/23 das amostras de solo coletadas de praças públicas. A contaminação somente por ovos de Ancylostoma sp. em amostras de solo coletadas em escolas/creches foi de 22,2% (4/18. A percentagem de amostras de areia coletadas de escolas/creches contaminadas somente com larvas de Ancylostoma sp. foi de 11,1% (2/18. Praças públicas são as áreas com maior risco potencial de infecção por Toxocara sp. e Ancylostoma sp. Exame coproparasitológico realizado em 174 amostras de fezes de cães observou 58% e 23%, respectivamente, com ovos de Ancylostoma sp. e Toxocara sp.Visceral and cutaneous larva migrans are parasitic zoonoses caused by the infection of larval nematodes Toxocara sp. and Ancylostoma sp. respectively. The objective of this study was to investigate the contamination by Toxocara sp. eggs and Ancylostoma sp. eggs and larva of soil samples collected from public parks and children's playground areas in state of Minas Gerais, Brazil, using both Baermann's method and centrifugal flotation technique. Toxocara sp. and Ancylostoma sp. eggs were observed in soil samples collected from public squares in 17.4% (4/23 and 69.6 (16/23 respectively. In schools and child day care settings the contamination by Ancylostoma sp. larva in sand samples was 11.1% (2/18. Public parks are settings of more potential risk of Toxocara sp. eggs and Ancylostoma sp. infection. Stool parasitology testing of 174 stool

  19. Microalgae associated Brevundimonas sp. MSK 4 as the nano particle synthesizing unit to produce antimicrobial silver nanoparticles

    Science.gov (United States)

    Rajamanickam, Karthic; Sudha, S. S.; Francis, Mebin; Sowmya, T.; Rengaramanujam, J.; Sivalingam, Periyasamy; Prabakar, Kandasamy

    2013-09-01

    The biosynthesis of silver nanoparticles and its antimicrobial property was studied using bacteria isolated from Spirulina products. Isolated bacteria were identified as Bacillus sp. MSK 1 (JX495945), Staphylococcus sp. MSK 2 (JX495946), Bacillus sp. MSK 3 (JX495947) and Brevundimonas sp. MSK 4 (JX495948). Silver nanoparticles (AgNPs) were synthesized using bacterial culture filtrate with AgNO3. The initial syntheses of Ag nanoparticles were characterized by UV-vis spectrophotometer (by measuring the color change to intense brown). Fourier Transform Infrared Spectroscopy (FTIR) study showed evidence that proteins are possible reducing agents and Energy-dispersive X-ray (EDX) study showing the metal silver as major signal. The structure of AgNPs was determined by Scanning electron microscopy (SEM) and X-ray diffraction (XRD). Synthesized Ag nanoparticles with an average size of 40-65 nm have antimicrobial property against human pathogens like Proteus vulgaris, Salmonella typhi, Vibrio cholera, Streptococcus sp., Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. Among the isolates Brevundimonas sp. MSK 4 alone showed good activity in both synthesis of AgNPs and antimicrobial activity. This work demonstrates the possible use of biological synthesized silver nanoparticles to combat the drug resistant problem.

  20. Nanodiamond composite as a material for cold electron emitters

    Energy Technology Data Exchange (ETDEWEB)

    Arkhipov, A V; Sominski, G G; Uvarov, A A [St.Petersburg State Polytechnic University, 29 Politchnicheskaya, St.Petersburg, 195251 (Russian Federation); Gordeev, S K; Korchagina, S B [FSUE ' Central Research Institute for Materials' , 8 Paradnaya Street, St.Petersburg, 191014 (Russian Federation)], E-mail: arkhipov@rphf.spbstu.ru

    2008-03-15

    Characteristics of field-induced electron emission were investigated for one of newly designed all-carbon materials - nanodiamond composite (NDC). The composite is comprised by 4-6 nm diamond grains covered with 0.2-1 nm-thick graphite-like shells that merge at grain junctions and determine such properties as mechanical strength and high electric conductivity. Large number of uniformly distributed sp{sup 3}-sp{sup 2} interfaces allowed to expect enhanced electron emission in electric field. Combination of these features makes NDC a promising material for cold electron emitters in various applications. Experimental testing confirmed high efficiency of electron emission from NDC. In comparison with previousely tested forms of nanocarbon, NDC emitters demonstrated better stabily and tolerance to performance conditions. Unusual activation scenarios and thermal dependencies of emission characteristics observed in experiments with NDC can add new background for explanation of facilitated electron emission from nanocarbons with relatively 'smooth' surface morphology.

  1. Ultrastructural identification of Ehrlich ia sp in an experimentally infected dog in Venezuela

    International Nuclear Information System (INIS)

    Gutierrez, N.; Martinez, M.; Arraga Alvarado, C.; Bretana, A.; Pacheco, I.; Comach, G.

    1999-01-01

    This study is the first report made in Venezuela concerning the ultrastructural characteristics of Ehrlich ia sp in mononuclear blood cells from an experimentally infected dog. The animal developed clinical manifestations characteristic of the infection, and typical intracytoplasmic inclusion bodies were clearly seen in blood smears stained with modified Giemsa examined by light microscopy. Microorganisms were visualized by transmission electron microscopy. The cytoplasmic inclusions, consisted of membrane-lined vacuole-containing elementary bodies. The organisms were extremely pleomorphic. Elementary bodies were surrounded by two distinct membranes and each was constituted by electro-dense granules. These findings corresponded to the described electron microscopy morphology which characterizes the Ehrlich ia genus

  2. Nitrogen fixation in Asaia sp. (family Acetobacteraceae).

    Science.gov (United States)

    Samaddar, Neeloy; Paul, Arundhati; Chakravorty, Somnath; Chakraborty, Writachit; Mukherjee, Joydeep; Chowdhuri, Debarati; Gachhui, Ratan

    2011-08-01

    The genus Asaia (family Acetobacteraceae) was first introduced with a single species-Asaia bogorensis and later six more species were described namely A. siamensis, A. krungthepensis, A. lannaensis, A. platycodi, A. prunellae, and A. astilbes. Acetobacteraceae family has been divided into ten genera but, only three of them include nitrogen fixing species: Gluconacetobacter, Acetobacter, and Swaminathania. This article originated from our study primarily aimed to isolate new endosymbiotic nitrogen fixer among Acetobacteraceae during which we have isolated, for the first time in India, four different strains of Asaia sp. from three different sources: Michalia champaca flower, Anopheles mosquito, and ant Tetraponera rufonigra. All the endosymbiotic strains isolated possess the ability to fix nitrogen. Evidence for both nitrogenase activity and the presence of nifH gene in isolated Asaia sp. is presented. Asaia bogorensis (MTCC 4041(T)) and A. siamensis (MTCC 4042(T)), two of the validated type strains available from the repository, were tested positive for the presence of functional nitrogenase. The nifH gene sequences from these type strains were also confirmed and compared with other nitrogen fixing members of the family Acetobacteraceae. Our result corroborate with the previous reports that Asaia sp. are indeed widely distributed in nature but this is the first time demonstration of their functional nitrogenase activity. This study shows Asaia sp. as fourth genera of nitrogen fixing bacteria in the family Acetobacteraceae.

  3. Molecular characterization of Trichoderma sp. isolated from ...

    African Journals Online (AJOL)

    The genetic relatedness among 15 isolates of Trichoderma sp. was analyzed with six micro-satellite primers. ISSR profiles showed 83.7% genetic diversity among the isolates with the formation of four clusters. Analysis of dendrogram revealed that similarity coefficient ranged from 0.27 to 0.95. ITS-PCR of rDNA region with ...

  4. Som man spørger

    DEFF Research Database (Denmark)

    Bjerg, Lars

    Indhold: Input og outputinterview ; Tre interviewtyper ; Tre grundprincipper ; De syv dødssynder ; Åbne, simple og neutrale spørgsmål ; Skuffespørgsmål ; Fokus ; Aktiv lytning ; Mål ; Strategi ; Abstrakt og konkret ; Det kritiske interview ; Kilder med et budskab ; Oldfruens fif ; Resumé i punktform...

  5. POTENSI MELANOTUS SP. DALAM MENDEGRADASI LIGNIN

    Directory of Open Access Journals (Sweden)

    NUNIK SULISTINAH

    2008-06-01

    Full Text Available Ten isolates of fungus were isolated from oil palm stem at oil palm plantation in Medan All of them were tested its abilities to degrade lignin. The results showed that one of them was able to grow on ligninase media and the fungi has the ability to degrade ligin. The fungi is identified as Melanotus sp.

  6. Biosorption of uranium by Azolla, SP, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Ludmila C.; Alves, Eliakim G.; Marumo, Julio T., E-mail: lcvieira@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Ferreira, Rafael V. de P., E-mail: rafael@itatijuca.com [Itatijuca Biotech, Sao Paulo, SP (Brazil); Canevesi, Rafael L.S.; Silva, Edson A., E-mail: edson.silva2@unioeste.br [Universidade Estadual do Oeste Parana (UNIOESTE), Toledo, PR (Brazil)

    2015-07-01

    Radioactive liquid waste needs special attention and requires suitable treatment before deposition. Among the potential technologies under development for the treatment of liquid radioactive wastes the biosorption has been highlighted by being an efficient and low cost technique. Biosorption process involves the exchange of ions contained in the biomass matrix by others present in solution. There are many biomasses that could be applied in treatment of radioactive wastes, for example, agricultural residues and macrophyte. The aim of this study is evaluate the ability of the Azolla sp., a floating aquatic plant, to absorb uranium in solution. Azolla sp. is a macrophyte that has been used to treat effluents containing heavy metals. The biosorption capacity of uranium by Azolla sp. was experimentally determined and modeled by isotherms. Experiments were performed to determine metal uptake, and then the solutions were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). The isotherms applied to model the data was Langmuir, Freundlich, Sips Toth, Redlich Peternson, Two-Site-Langmuir, Radke Prausnitz to develop a technique for the treatment of radioactive liquid waste generated at the Nuclear and Energy Research Institute (IPEN-CNEN/SP), Brazil. (author)

  7. Biosorption of uranium by Azolla, SP, Brazil

    International Nuclear Information System (INIS)

    Vieira, Ludmila C.; Alves, Eliakim G.; Marumo, Julio T.; Ferreira, Rafael V. de P.; Canevesi, Rafael L.S.; Silva, Edson A.

    2015-01-01

    Radioactive liquid waste needs special attention and requires suitable treatment before deposition. Among the potential technologies under development for the treatment of liquid radioactive wastes the biosorption has been highlighted by being an efficient and low cost technique. Biosorption process involves the exchange of ions contained in the biomass matrix by others present in solution. There are many biomasses that could be applied in treatment of radioactive wastes, for example, agricultural residues and macrophyte. The aim of this study is evaluate the ability of the Azolla sp., a floating aquatic plant, to absorb uranium in solution. Azolla sp. is a macrophyte that has been used to treat effluents containing heavy metals. The biosorption capacity of uranium by Azolla sp. was experimentally determined and modeled by isotherms. Experiments were performed to determine metal uptake, and then the solutions were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). The isotherms applied to model the data was Langmuir, Freundlich, Sips Toth, Redlich Peternson, Two-Site-Langmuir, Radke Prausnitz to develop a technique for the treatment of radioactive liquid waste generated at the Nuclear and Energy Research Institute (IPEN-CNEN/SP), Brazil. (author)

  8. Lipid contents of the sponge Haliclona sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Parameswaran, P.S.; Das, B.; Kamat, S.Y.

    Several fatty acids, sterols, batyl alcohol and its analogs and an N-acylated sphingosine (ceramide) have been isolated from the lipid fraction of the extract of the sponge Haliclona sp. The major sterol is found to be cholesterol (54%), followed...

  9. Test af spørgeskema

    DEFF Research Database (Denmark)

    Hermansen, Jonathan

    2017-01-01

    Denne bog gennemgår alle surveyarbejdets faser og giver en praktisk indføring i •design af undersøgelsen og udvælgelse af stikprøver, •formulering af spørgeskemaer samt indsamling og kodning af data, •metoder til at analysere resultaterne....

  10. Botrallin from the endophytic fungus Hyalodendriella sp ...

    African Journals Online (AJOL)

    use

    2011-12-12

    Dec 12, 2011 ... Bioassay-guided fractionation of the crude methanol extract of the mycelia from the endophytic fungus. Hyalodendriella sp. Ponipodef12, associated with the hybrid 'Neva' of Populus deltoides Marsh × P. nigra L., led to the isolation of one compound coded as P12-1 which was identified as botrallin (1,7-.

  11. Electronic Commerce and Electronic Business

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    This special issue is motivated by the recent upsurge of research activity in the areas of electronic commerce and electronic business both in India and all over the world. The current research activity is quite intensive in the use of mathematical tools such as cryptography, game theory, mechanism design, optimization, ...

  12. Electronic identity

    CERN Document Server

    de Andrade, Norberto Nuno Gomes; Argles, David

    2014-01-01

    With the increasing availability of electronic services, security and a reliable means by which identity is verified is essential.Written by Norberto Andrade the first chapter of this book provides an overview of the main legal and regulatory aspects regarding electronic identity in Europe and assesses the importance of electronic identity for administration (public), business (private) and, above all, citizens. It also highlights the role of eID as a key enabler of the economy.In the second chapter Lisha Chen-Wilson, David Argles, Michele Schiano di Zenise and Gary Wills discuss the user-cent

  13. Electronic diagrams

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Diagrams is a ready reference and general guide to systems and circuit planning and in the preparation of diagrams for both newcomers and the more experienced. This book presents guidelines and logical procedures that the reader can follow and then be equipped to tackle large complex diagrams by recognition of characteristic 'building blocks' or 'black boxes'. The goal is to break down many of the barriers that often seem to deter students and laymen in learning the art of electronics, especially when they take up electronics as a spare time occupation. This text is comprised of nin

  14. Digital electronics

    CERN Document Server

    Morris, John

    2013-01-01

    An essential companion to John C Morris's 'Analogue Electronics', this clear and accessible text is designed for electronics students, teachers and enthusiasts who already have a basic understanding of electronics, and who wish to develop their knowledge of digital techniques and applications. Employing a discovery-based approach, the author covers fundamental theory before going on to develop an appreciation of logic networks, integrated circuit applications and analogue-digital conversion. A section on digital fault finding and useful ic data sheets completes th

  15. Starting electronics

    CERN Document Server

    Brindley, Keith

    2005-01-01

    Starting Electronics is unrivalled as a highly practical introduction for hobbyists, students and technicians. Keith Brindley introduces readers to the functions of the main component types, their uses, and the basic principles of building and designing electronic circuits. Breadboard layouts make this very much a ready-to-run book for the experimenter; and the use of multimeter, but not oscilloscopes, puts this practical exploration of electronics within reach of every home enthusiast's pocket. The third edition has kept the simplicity and clarity of the original. New material

  16. Polymer electronics

    CERN Document Server

    Geoghegan, Mark

    2013-01-01

    Polymer electronics is the science behind many important new developments in technology, such as the flexible electronic display (e-ink) and many new developments in transistor technology. Solar cells, light-emitting diodes, and transistors are all areas where plastic electronics is likely to, or is already having, a serious impact on our daily lives. With polymer transistors and light-emitting diodes now being commercialised, there is a clear need for a pedagogic text thatdiscusses the subject in a clear and concise fashion suitable for senior undergraduate and graduate students. The content

  17. Stretchable electronics

    CERN Document Server

    Someya, Takao

    2012-01-01

    With its comprehensive coverage this handbook and ready reference brings together some of the most outstanding scientists in the field to lay down the undisputed knowledge on how to make electronics stretchable.As such, it focuses on gathering and evaluating the materials, designs, models and technologies that enable the fabrication of fully elastic electronic devices which can sustain high strain. Furthermore, it provides a review of those specific applications that directly benefit from highly compliant electronics, including transistors, photonic devices and sensors. In addition to stre

  18. C (sp2)–C (sp2) cross coupling reaction catalyzed by a palladacycle ...

    Indian Academy of Sciences (India)

    (sp2) cross coupling reaction catalyzed by a palladacycle phosphine complex: A simple and sustainable protocol in aqueous media. Seyyed Javad Sabounchei Marjan Hosseinzadeh. Articles Volume 127 Issue 11 November 2015 pp 1919- ...

  19. Nanocrystalline sp{sup 2} and sp{sup 3} carbons: CVD synthesis and applications

    Energy Technology Data Exchange (ETDEWEB)

    Terranova, M. L. [Università degli Studi di Roma “Tor Vergata,” via Della Ricerca Scientifica, Dipartimento di Scienze e Tecnologie Chimiche—MinimaLab (Italy); Rossi, M. [Università degli Studi di Roma “Sapienza,” via A. Scarpa, Dipartimento di Scienze di Base e Applicate per l’Ingegneria and Centro di Ricerca per le Nanotecnologie Applicate all’Ingegneria (CNIS) (Italy); Tamburri, E., E-mail: emanuela.tamburri@uniroma2.it [Università degli Studi di Roma “Tor Vergata,” via Della Ricerca Scientifica, Dipartimento di Scienze e Tecnologie Chimiche—MinimaLab (Italy)

    2016-11-15

    The design and production of innovative materials based on nanocrystalline sp{sup 2}- and sp{sup 3}-coordinated carbons is presently a focus of the scientific community. We present a review of the nanostructures obtained in our labs using a series of synthetic routes, which make use of chemical vapor deposition (CVD) techniques for the selective production of non-planar graphitic nanostructures, nanocrystalline diamonds, and hybrid two-phase nanostructures.

  20. Analisis Fosfor pada Cacing Tanah (Megascolex sp. dan Fridericia sp.) Secara Spektrofotometri Sinar Tampak

    OpenAIRE

    Safira, Cut Shafa

    2015-01-01

    Earthworm is natural resource which can be used for medication due to its highly amount of minerals. One of these minerals is phosphorus. The aim of this research are to identify, determine and know the difference content of phosphorus in Megascolex sp. and Fridericia sp. Qualitative analysis shows positive results with addition of ammonium molybdate 4% and BaCl2 5%. Quantitative analysis was done using visible spectrophotometer with ascorbic acid method, measuring blu-colored molybdenum ...