The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
Denis J Murphy - One of the best experts on this subject based on the ideXlab platform.
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biochemical transcriptional and bioinformatic analysis of lipid droplets from seeds of date palm phoenix dactylifera l and their use as potent sequestration agents against the Toxic Pollutant 2 3 7 8 tetrachlorinated dibenzo p dioxin
Frontiers in Plant Science, 2016Co-Authors: Abdulsamie Hanano, Ibrahem Almousally, Mouhnad Shaban, Farzana Rahman, Elizabeth Blee, Denis J MurphyAbstract:Contamination of aquatic environments with dioxins, the most Toxic group of persistent organic Pollutants (POPs), is a major ecological issue. Dioxins are highly lipophilic and bioaccumulate in fatty tissues of marine organisms used for seafood where they constitute a potential risk for human health. Lipid droplets (LDs) purified from date palm, Phoenix dactylifera, seeds were characterised and their capacity to extract dioxins from aquatic systems was assessed. The bioaffinity of date palm LDs towards 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most Toxic congener of dioxins was determined. Fractioned LDs were spheroidal with mean diameters of 2.5 m, enclosing an oil-rich core of 392.5 mg.mL-1. Isolated LDs did not aggregate and/or coalesce unless placed in acidic media and were strongly associated with three major groups of polypeptides of relative mass 32-37, 20-24 and 16-18 kDa. These masses correspond to the LD-associated proteins, oleosins, caleosins and steroleosins, respectively. Efficient partitioning of TCDD into LDs occurred with a coefficient of log KLB/w,TCDD = 7.528 ± 0.024; it was optimal at neutral pH and was dependent on the presence of the oil-rich core, but was independent of the presence of LD-associated proteins. Bioinformatic analysis of the date palm genome revealed 9 oleosin-like, 5 caleosin-like, and 5 steroleosin-like sequences, with predicted structures having putative lipid-binding domains that match their LD stabilising roles and use as bio-based encapsulation systems. Transcriptomic analysis of date palm seedlings exposed to TCDD showed strong up-regulation of several caleosin and steroleosin genes, consistent with increased LD formation. The results suggest that the plant LDs could be used in ecological remediation strategies to remove POPs from aquatic environments. Recent reports suggest that several fungal and algal species also use LDs to sequester both external and internally derived hydrophobic toxins, which indicates that our approach could be used as a broader biomimetic strategy for toxin removal.
Irene Klontza - One of the best experts on this subject based on the ideXlab platform.
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Testing phenanthrene distribution properties of virgin plastic pellets and plastic eroded pellets found on Lesvos island beaches (Greece)
Marine Environmental Research, 2008Co-Authors: Hrissi K. Karapanagioti, Irene KlontzaAbstract:Plastic pellets have been characterized as Toxic Pollutant carriers throughout the world oceans and coastal zones. However, their sorptive properties are not yet well understood. In the present study, virgin pellets and plastic eroded pellets (PEP) are used to elucidate their distribution characteristics through distribution kinetic studies. Distribution occurs through diffusion into the pellet for all materials (polyethylene, polyoxymethylene, and PEP) except polypropylene (PP). Although diffusion into the polymer happens with similar rates for both freshwater and saltwater external solutions, apparent diffusion is dependent on the solution salinity because it results in higher equilibrium distribution coefficients. Distribution coefficient into the PEP is higher and diffusion is slower than into the virgin materials. This is attributed to increased crystallinity of the PEP due to weathering. PP demonstrates diffusion rates that are increased by salinity and is apparently faster than into the other polymers suggesting a surface diffusion process. © 2007 Elsevier Ltd. All rights reserved.
Abdulsamie Hanano - One of the best experts on this subject based on the ideXlab platform.
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biochemical transcriptional and bioinformatic analysis of lipid droplets from seeds of date palm phoenix dactylifera l and their use as potent sequestration agents against the Toxic Pollutant 2 3 7 8 tetrachlorinated dibenzo p dioxin
Frontiers in Plant Science, 2016Co-Authors: Abdulsamie Hanano, Ibrahem Almousally, Mouhnad Shaban, Farzana Rahman, Elizabeth Blee, Denis J MurphyAbstract:Contamination of aquatic environments with dioxins, the most Toxic group of persistent organic Pollutants (POPs), is a major ecological issue. Dioxins are highly lipophilic and bioaccumulate in fatty tissues of marine organisms used for seafood where they constitute a potential risk for human health. Lipid droplets (LDs) purified from date palm, Phoenix dactylifera, seeds were characterised and their capacity to extract dioxins from aquatic systems was assessed. The bioaffinity of date palm LDs towards 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most Toxic congener of dioxins was determined. Fractioned LDs were spheroidal with mean diameters of 2.5 m, enclosing an oil-rich core of 392.5 mg.mL-1. Isolated LDs did not aggregate and/or coalesce unless placed in acidic media and were strongly associated with three major groups of polypeptides of relative mass 32-37, 20-24 and 16-18 kDa. These masses correspond to the LD-associated proteins, oleosins, caleosins and steroleosins, respectively. Efficient partitioning of TCDD into LDs occurred with a coefficient of log KLB/w,TCDD = 7.528 ± 0.024; it was optimal at neutral pH and was dependent on the presence of the oil-rich core, but was independent of the presence of LD-associated proteins. Bioinformatic analysis of the date palm genome revealed 9 oleosin-like, 5 caleosin-like, and 5 steroleosin-like sequences, with predicted structures having putative lipid-binding domains that match their LD stabilising roles and use as bio-based encapsulation systems. Transcriptomic analysis of date palm seedlings exposed to TCDD showed strong up-regulation of several caleosin and steroleosin genes, consistent with increased LD formation. The results suggest that the plant LDs could be used in ecological remediation strategies to remove POPs from aquatic environments. Recent reports suggest that several fungal and algal species also use LDs to sequester both external and internally derived hydrophobic toxins, which indicates that our approach could be used as a broader biomimetic strategy for toxin removal.
Claudia Copeland - One of the best experts on this subject based on the ideXlab platform.
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Clean water act: A summary of the law
Atmospheric Deposition of Pollutants and the EPA, 2012Co-Authors: Claudia CopelandAbstract:The principal law governing pollution of the nation's surface waters is the Federal Water Pollution Control Act, or Clean Water Act.Originally enacted in 1948, it was totally revised by amendments in 1972 that gave the act its current dimensions. The 1972 legislation spelled out ambitious programs for water quality improvement that have since been expanded and are still being implemented by industries and municipalities.This report presents a summary of the law, describing the statute without discussing its implementation.The Clean Water Act consists of two major parts, one being the provisions which authorize federal financial assistance for municipal sewage treatment plant construction. The other is the regulatory requirements that apply to industrial and municipal dischargers. The act has been termed a technology-forcing statute because of the rigorous demands placed on those who are regulated by it to achieve higher and higher levels of pollution abatement under deadlines specified in the law.Early on, emphasis was on controlling discharges of conventionalPollutants (e.g., suspended solids or bacteria that are biodegradable and occur naturally in the aquatic environment), while control of Toxic Pollutant discharges has been a key focus of water quality programs more recently.Prior to 1987, programs were primarily directed at point source pollution, that is, wastes discharged from discrete sources such as pipes and outfalls. Amendments to the law in that year authorized measures to address nonpoint source pollution (runoff from farm lands, forests, construction sites, and urban areas), which is estimated to represent more than 50% of the nation's remaining water pollution problems. The act also prohibits discharge of oil and hazardous substances into U.S. waters.Under this act, federal jurisdiction is broad, particularly regarding establishment of national standards or effluent limitations. Certain responsibilities are delegated to the states, and the act embodies a philosophy of federal-state partnership in which the federal government sets the agenda and standards for pollution abatement, while states carry out day-to-day activities of implementation and enforcement.To achieve its objectives, the act is based on the concept that all discharges into the nation's waters are unlawful, unless specifically authorized by a permit, which is the act's principal enforcement tool. The law has civil, criminal, and administrative enforcement provisions and also permits citizen suit enforcement. Financial assistance for constructing municipal sewage treatment plants and certain other types of water quality improvements projects is authorized under title VI. It authorizes grants to capitalize State Water Pollution Control Revolving Funds, or loan programs. States contribute matching funds, and under the revolving loan fund concept, monies used for wastewater treatment construction are repaid to states, to be available for future construction in other communities.
Hrissi K. Karapanagioti - One of the best experts on this subject based on the ideXlab platform.
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Testing phenanthrene distribution properties of virgin plastic pellets and plastic eroded pellets found on Lesvos island beaches (Greece)
Marine Environmental Research, 2008Co-Authors: Hrissi K. Karapanagioti, Irene KlontzaAbstract:Plastic pellets have been characterized as Toxic Pollutant carriers throughout the world oceans and coastal zones. However, their sorptive properties are not yet well understood. In the present study, virgin pellets and plastic eroded pellets (PEP) are used to elucidate their distribution characteristics through distribution kinetic studies. Distribution occurs through diffusion into the pellet for all materials (polyethylene, polyoxymethylene, and PEP) except polypropylene (PP). Although diffusion into the polymer happens with similar rates for both freshwater and saltwater external solutions, apparent diffusion is dependent on the solution salinity because it results in higher equilibrium distribution coefficients. Distribution coefficient into the PEP is higher and diffusion is slower than into the virgin materials. This is attributed to increased crystallinity of the PEP due to weathering. PP demonstrates diffusion rates that are increased by salinity and is apparently faster than into the other polymers suggesting a surface diffusion process. © 2007 Elsevier Ltd. All rights reserved.
