699 research outputs found

    Microbial Enrichment of a Novel Growing Substrate and its Effect on Plant Growth

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    The quality of torrefied grass fibers (TGF) as a new potting soil ingredient was tested in a greenhouse experiment. TGF was colonized with previously selected microorganisms. Four colonization treatments were compared: (1) no inoculants, (2) the fungus Coniochaeta ligniaria F/TGF15 alone, (3) the fungus followed by inoculation with two selected bacteria, and (4) the fungus with seven selected bacteria. Cultivation-based and DNA-based methods, i.e., PCR-DGGE and BOX-PCR, were applied to assess the bacterial and fungal communities established in the TGF. Although colonization was not performed under sterile conditions, all inoculated strains were recovered from TGF up to 26 days incubation. Stable fungal and bacterial populations of 108 and 109 CFU/g TGF, respectively, were reached. As a side effect of the torrefaction process that aimed at the chemical stabilization of grass fibers, potentially phytotoxic compounds were generated. These phytotoxic compounds were cold-extracted from the fibers and analyzed by gas chromatography mass spectrometry. Four of 15 target compounds that had previously been found in the extract of TGF were encountered, namely phenol, 2-methoxyphenol, benzopyran-2-one, and tetrahydro-5,6,7,7a-benzofuranone. The concentration of these compounds decreased significantly during incubation. The colonized TGF was mixed with peat (P) in a range of 100%:0%, 50%:50%, 20%:80%, and 0%:100% TGF/P (w/w), respectively, to assess suitability for plant growth. Germination of tomato seeds was assessed three times, i.e., with inoculated TGF that had been incubated for 12, 21, and 26 days. In these tests, 90–100% of the seeds germinated in 50%:50% and 20%:80% TGF/P, whereas on average only 50% of the seeds germinated in pure TGF. Germination was not improved by the microbial inoculants. However, plant fresh weight as well as leaf area of 28-day-old tomato plants were significantly increased in all treatments where C. ligniaria F/TGF15 was inoculated compared to the control treatment without microbial inoculants. Colonization with C. ligniaria also protected the substrate from uncontrolled colonization by other fungi. The excellent colonization of TGF by the selected plant-health promoting bacteria in combination with the fungus C. ligniaria offers the possibility to create disease suppressive substrate, meanwhile replacing 20% to 50% of peat in potting soil by TGF

    Extracellular redox cycling and hydroxyl radical production occurs widely in lichenized Ascomycetes

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    © 2017 British Mycological Society.Some free-living Ascomycetes and white and brown rot Basidiomycetes can generate hydroxyl radicals using extracellular redox cycling. However, the mechanisms of hydroxyl radical production differ between white and brown rot Basidiomycetes, and are unknown for Ascomycetes. Here, we present a survey of extracellular hydroxyl radical production by a range of lichenized Ascomycetes. Results show that given a quinone and chelated ferric ions, many lichens can readily produce hydroxyl radicals, and this is accompanied by the reduction of Fe3+ to Fe2+. In white rot fungi, extracellular redox enzymes have been proposed to be involved in hydroxyl radical generation. However, a survey of a wide range of lichens suggests that in these fungi hydroxyl radical production does not directly correlate with the activity of laccases and peroxidases. Rather, radicals are probably produced by a mechanism like that proposed for brown rot fungi. Potential roles of hydroxyl radicals produced by lichens include the breakdown of lignocellulosic residues in the soil which may allow lichens to live a partially saprotrophic existence, the breakdown of toxic soil chemicals and the formation of an 'oxidative burst' to deter potential pathogens

    Extracellular redox cycling and hydroxyl radical production occurs widely in lichenized Ascomycetes

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    © 2017 British Mycological SocietySome free-living Ascomycetes and white and brown rot Basidiomycetes can generate hydroxyl radicals using extracellular redox cycling. However, the mechanisms of hydroxyl radical production differ between white and brown rot Basidiomycetes, and are unknown for Ascomycetes. Here, we present a survey of extracellular hydroxyl radical production by a range of lichenized Ascomycetes. Results show that given a quinone and chelated ferric ions, many lichens can readily produce hydroxyl radicals, and this is accompanied by the reduction of Fe3+ to Fe2+. In white rot fungi, extracellular redox enzymes have been proposed to be involved in hydroxyl radical generation. However, a survey of a wide range of lichens suggests that in these fungi hydroxyl radical production does not directly correlate with the activity of laccases and peroxidases. Rather, radicals are probably produced by a mechanism like that proposed for brown rot fungi. Potential roles of hydroxyl radicals produced by lichens include the breakdown of lignocellulosic residues in the soil which may allow lichens to live a partially saprotrophic existence, the breakdown of toxic soil chemicals and the formation of an ‘oxidative burst’ to deter potential pathogens

    Network approaches for formalizing conceptual models in ecosystem-based management

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    Funding Intermodel comparisons were supported through funding from the NOAA Integrated Ecosystem Assessment Program. P.S. McDonald’s involvement was funded in part by a grant from Washington Sea Grant, University of Washington, pursuant to National Oceanic and Atmospheric Administration Award number NA14OAR4170078. Funding for RPW was supported by the National Marine Fisheries Service (NMFS)/Sea Grant Population and Ecosystem Dynamics Graduate Fellowship via federal award NA14OAR4170077. Acknowledgements We would like to acknowledge and thank the participants of the NOAA Integrated Ecosystem Assessment Program conceptual network modelling workshop at Baton Rouge, LA in July 2018. The discussions at this meeting formed some of the basis for the ideas presented in this manuscript. We also thank J. Moss and two anonymous reviewers for valuable comments on earlier manuscript drafts. The findings and conclusions in this article are those of the authors and do not necessarily represent the views of the National Marine Fisheries Service, NOAA. Reference to trade names does not imply endorsement by the National Marine Fisheries Service, NOAA. This is NOAA Integrated Ecosystem Assessment Program contribution number 2021_3.Peer reviewedPostprin

    CARCINOGENIC ACTION OF AROMATIC AMINES

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    Nowadays, people are increasingly exposed to various carcinogenic factors. The problem of carcinogenic effects is relevant, since with the development of modern sciences a detailed study of the problem, the action of pathogenic factors, mechanisms and, most importantly, methods of dealing with this problem are possible.В настоящее время люди все чаще подвергаются воздействию различных канцерогенных факторов. Проблема канцерогенного воздействия является актуальной, так как с развитием современных наук возможно детальное изучение проблемы, действия патогенных факторов, механизмов и самое главное – методов борьбы с данной проблемой

    Biochemical characterization of peroxidases from the moss Dicranum scoparium

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    © 2018 South African Association of Botanists Mosses are a convenient model to study stress responses of plants because of their remarkable stress tolerance. Peroxidase (EC 1.11.1.7) activities were tested in three moss species, namely Dicranum scoparium, Hylocomium splendens and Pleurozium schreberi growing together in the same location in a boreal forest. Peroxidase activity in D. scoparium was twice as high as in other mosses. Total peroxidase activity in unstressed D. scoparium was constitutively high; furthermore, long-term desiccation caused a significant increase in activity after 48 h of drying. Interestingly, when thalli desiccated for a week were rapidly rehydrated, peroxidase activity initially declined and then increased after 2 h rehydration. Diverse anionic and cationic isoforms were detected by native isoelectric focusing and PAGE of both crude extracts and partially purified peroxidases. The ability of peroxidases from D. scoparium to produce superoxide radical (O2•−) was confirmed using the 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) reduction assay and in-gel nitroblue tetrazolium chloride (NBT) staining; specific O2•−producing isoforms were revealed using 2D electrophoresis. Given a quinone and chelated Fe3+D. scoparium could produce extracellular hydroxyl radical (•OH), and production was increased by desiccation/rehydration stress. The possible roles of peroxidases and quinone reductases in apoplastic•OH production is discussed. Our data demonstrate that D. scoparium possesses high constitutive peroxidase activity that can be further increased by desiccation stress. Among the diverse moss peroxidases, some anionic isoforms displayed both pro- and antioxidative activities. These findings suggest that the ability of peroxidases to produce and detoxify reactive oxygen species is an evolutionarily ancient characteristic, important for plant stress tolerance

    BLOOD LIPOPROTEINS AS A PLATFORM FOR TRANSPORT OF HYDROPHILIC AND HYDROPHOBIC COMPOUNDS

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    The paper discusses the transport functions of the main classes of blood plasma lipoproteins (LP) that are not associated with the metabolism of lipids that make up their composition. The aim of the study was to study the ability of various plasma LP fractions (very low (VLDL), low (LDL) and high density (HDL)) to interact with certain hydrophilic and hydrophobic compounds and show the role of LP as transport forms of xenobiotics in the organs and tissues of the body. Material and methods. The studies were performed with tritium-labeled cytochalasin B, benzylpenicillin, benzanthracene, benzo(a)pyrene, ultracentrifugation of human plasma LP fractions, column chromatography; in vivo experiments with intravenous injection of LP complexes with tritium-labeled benzanthracene were conducted. Results. The ability of various classes of LP to form complexes with hydrophilic (cytochalasin B, benzylpenicillin) and hydrophobic (benzanthracene, benzo(a)pyrene) compounds is shown by the method of ultracentrifugation. More than 50 % of the radioactivity of hydrophilic compounds in human blood plasma was represented in the composition of the LDL and HDL fractions, and in the composition of the VLDL fractions it was minimal – 6.3 and 5.1 %, respectively. A significant part of cytochalasin and benzylpenicillin was also present in the protein infranatant – 43.6 and 40.9 %, respectively. The distribution in blood plasma for hydrophobic (benzanthracene, benzo(a)pyrene) compounds was different. More than 80 % of the radioactivity was represented in the composition of the LP fractions. The polar protein infranatant contained 16.1 % of the radioactivity of benzantracene and 13.6 % of benzo(a)pyrene. The features of the lipophilic xenobiotics uptake by organs and tissues were shown in vivo experiments with intravenous injection of complexes of LP with tritium-labeled benzanthracene to rats. The highest specific radioactivity was found in the liver and adrenal glands after the intravenous injection of 3H-benzanthracene in the composition of VLDL and LDL. Twice less uptake of the labeled drug was observed in the testis and kidneys. Radioactivity decreased in the series: lungs,adipose tissue, thymus, heart, and spleen. A feature of the use of HDL as a platform for 3H-enzanthracene is the intense accumulation of lipophilic xenobiotics in steroid-producing organs: the adrenal glands and testis. Conclusion. The results obtained allow us to consider the real possibility of using blood plasma PL as transport platforms for hydrophilic and hydrophobic compounds into the cells of organs and tissues

    Uptake of cholesterol esters being a part of the different fractions of blood plasma lipoproteins by rats organs and tissues

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    The paper deals with the functions of the main classes of blood plasma lipoproteins (LP) that are associated with the transport of cholesterol esters included in their composition. The aim of the study was to investigate the features of the uptake of cholesterol esters associated with plasma LP fractions (very low (VLDL), low (LDL), and high density LPs (HDL)) by rat organs and tissues, and to show the participation of various subfractions of HDL (HDL2 and HDL3) as specific cholesterol carriers in the main steroid-producing organs of rats.Material and methods. The in vivo studies with intravenous LP injection of 14C labeled cholesterol oleate (14C-OCh) associated with plasma LP fractions have been carried out.Results. Intravenous injection of a 14C-OCh) in the composition with VLDL led to the maximal mark uptake by the liver. Three times less uptake of labeled cholesterol was observed in the adrenal glands, testes and heart muscle. In other tissues radioactivity gradually decreased in the raw: spleen > lungs > kidneys > thyroid gland and adipose tissue. After the injection of 14C-OCh in the composition of LDL marked predominant uptake of the label by the adrenal glands, testes, and liver. A feature of the use of HDL as a carrier platform for 14C-OCh is the high accumulation of label in steroid-producing organs: the adrenal glands and testis. The dynamics of uptake of 14C-OCh in the composition of HDL by the adrenal glands and testes of rats in different time intervals after injection (30 min, 3, 6 and 12 h) was studied. Adrenal cells actively uptake 14C-OCh from HDL, as a result of which the radioactivity of the tissue increased rapidly and after 30 minutes almost reached its maximum. In contrast to the adrenal glands uptake of the testis was characterized by a gradual increase in radioactivity with a maximum of 6 hours and a rather sharp decrease to 12 hours from the beginning of the experiment. In vitro experiments showed the differences in the effect of HDL2 and HDL3 on the corticosterone production by the adrenal glands of rats.Conclusions. The paper presents the features of uptake of cholesterol esters by organs and tissues of rats depending on the used LP-transporter (VLDL, LDL, HDL). In addition, the results suggest that HDL3 subfraction may be the more preferred source of cholesterol for steroid synthesis in the adrenal cortex of rats compared to HDL2 subfraction

    An approach to assess flooding and erosion risk for open beaches in a changing climate

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    This paper examines the vulnerability to flooding and erosion of four open beach study sites in Europe. A framework for the quantitative estimation of present and future coastal flood and erosion risks is established using methods, data and tools from across a range of disciplines, including topographic and bathymetric data, climate data from observation, hindcast and model projections, statistical modelling of current and future climates and integrated risk analysis tools. Uncertainties in the estimation of future coastal system dynamics are considered, as are the consequences for the inland systems. Different implementations of the framework are applied to the study sites which have different wave, tidal and surge climate conditions. These sites are: Santander, Spain—the Atlantic Ocean; Bellocchio, Italy—the Adriatic Sea; Varna, Bulgaria—the Black Sea; and the Teign Estuary, UK—the northern Atlantic Ocean. The complexity of each system is first simplified by sub-division into coastal "impact units" defined by homogeneity in the local key forcing parameters: wave, wind, tide, river discharge, run-off, etc. This reduces the simulation to that of a number of simpler linear problems which are treated by applying the first two components of the Source–Pathway–Receptor–Consequence (S–P–R–C) approach. The case studies reveal the flexibility of this approach, which is found useful for the rapid assessment of the risks of flooding and erosion for a range of scenarios and the likely effectiveness of flood defences

    Satellite data for the offshore renewable energy sector: Synergies and innovation opportunities

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    Can satellite data be used to address challenges currently faced by the Offshore Renewable Energy (ORE) sector? What benefit can satellite observations bring to resource assessment and maintenance of ORE farms? Can satellite observations be used to assess the environmental impact of offshore renewables leading towards a more sustainable ORE sector? This review paper faces these questions presenting a holistic view of the current interactions between satellite and ORE sectors, and future needs to make this partnership grow. The aim of the work is to start the conversation between these sectors by establishing a common ground. We present offshore needs and satellite technology limitations, as well as potential opportunities and areas of growth. To better understand this, the reader is guided through the history, current developments, challenges and future of offshore wind, tidal and wave energy technologies. Then, an overview on satellite observations for ocean applications is given, covering types of instruments and how they are used to provide different metocean variables, satellite performance, and data processing and integration. Past, present and future satellite missions are also discussed. Finally, the paper focuses on innovation opportunities and the potential of synergies between the ORE and satellite sectors. Specifically, we pay attention to improvements that satellite observations could bring to standard measurement techniques: assessing uncertainty, wind, tidal and wave conditions forecast, as well as environmental monitoring from space. Satellite–enabled measurement of ocean physical processes and applications for fisheries, mammals and birds, and habitat change, are also discussed in depth
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