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Tapan Chakrabarti - One of the best experts on this subject based on the ideXlab platform.

  • activated sludge is a potential source for production of Biodegradable Plastics from wastewater
    Environmental Technology, 2005
    Co-Authors: Anshuman Khardenavis, M.s. Kumar, Prabal K. Guha, Sandeep Narayan Mudliar, Tapan Chakrabarti
    Abstract:

    Increased utilization of synthetic Plastics caused severe environmental pollution due to their non-Biodegradable nature. In the search for environmentally friendly materials to substitute for conventional Plastics, different Biodegradable Plastics have been developed by microbial fermentations. However, limitations of these materials still exist due to high cost. This study aims at minimization of cost for the production of Biodegradable Plastics P(3HB) and minimization of environmental pollution. The waste biological sludge generated at wastewater treatment plants is used for the production of P(3HB) and wastewater is used as carbon source. Activated sludge was induced by controlling the carbon : nitrogen ratio to accumulate storage polymer. Initially polymer accumulation was studied by using different carbon and nitrogen sources. Maximum accumulation of polymer was observed with carbon source acetic acid and diammonium hydrogen phosphate (DAHP) as nitrogen source. Further studies were carried out to opt...

  • Activated sludge is a potential source for production of Biodegradable Plastics from wastewater
    Environmental technology, 2005
    Co-Authors: Anshuman Khardenavis, M.s. Kumar, Prabal K. Guha, Sandeep Narayan Mudliar, Tapan Chakrabarti
    Abstract:

    Increased utilization of synthetic Plastics caused severe environmental pollution due to their non-Biodegradable nature. In the search for environmentally friendly materials to substitute for conventional Plastics, different Biodegradable Plastics have been developed by microbial fermentations. However, limitations of these materials still exist due to high cost. This study aims at minimization of cost for the production of Biodegradable Plastics P(3HB) and minimization of environmental pollution. The waste biological sludge generated at wastewater treatment plants is used for the production of P(3HB) and wastewater is used as carbon source. Activated sludge was induced by controlling the carbon: nitrogen ratio to accumulate storage polymer. Initially polymer accumulation was studied by using different carbon and nitrogen sources. Maximum accumulation of polymer was observed with carbon source acetic acid and diammonium hydrogen phosphate (DAHP) as nitrogen source. Further studies were carried out to optimize the carbon: nitrogen ratios using acetic add and DAHP. A maximum of 65.84% (w/w) P(3HB) production was obtained at C/N ratio of 50 within 96 hours of incubation. © Selper Ltd, 2005.

  • production of Biodegradable Plastics from activated sludge generated from a food processing industrial wastewater treatment plant
    Bioresource Technology, 2004
    Co-Authors: Suresh M Kumar, Sandeep Narayan Mudliar, Krishna Reddy, Tapan Chakrabarti
    Abstract:

    Most of the excess sludge from a wastewater treatment plant (60%) is disposed by landfill. As a resource utilization of excess sludge, the production of Biodegradable Plastics using the sludge has been proposed. Storage polymers in bacterial cells can be extracted and used as Biodegradable Plastics. However, widespread applications have been limited by high production cost. In the present study, activated sludge bacteria in a conventional wastewater treatment system were induced, by controlling the carbon: nitrogen ratio to accumulate storage polymers. Polymer yield increased to a maximum 33% of biomass (w/w) when the C/N ratio was increased from 24 to 144, where as specific growth yield decreased with increasing C/N ratio. The conditions which are required for the maximum polymer accumulation were optimized and are discussed.

  • Production of Biodegradable Plastics from activated sludge generated from a food processing industrial wastewater treatment plant
    Bioresource Technology, 2004
    Co-Authors: M. Suresh Kumar, K. M.k. Reddy, Sandeep Narayan Mudliar, Tapan Chakrabarti
    Abstract:

    Most of the excess sludge from a wastewater treatment plant (60%) is disposed by landfill. As a resource utilization of excess sludge, the production of Biodegradable Plastics using the sludge has been proposed. Storage polymers in bacterial cells can be extracted and used as Biodegradable Plastics. However, widespread applications have been limited by high production cost. In the present study, activated sludge bacteria in a conventional wastewater treatment system were induced, by controlling the carbon: nitrogen ratio to accumulate storage polymers. Polymer yield increased to a maximum 33% of biomass (w/w) when the C/N ratio was increased from 24 to 144, where as specific growth yield decreased with increasing C/N ratio. The conditions which are required for the maximum polymer accumulation were optimized and are discussed. © 2004 Elsevier Ltd. All rights reserved.

Martin Zimmer - One of the best experts on this subject based on the ideXlab platform.

  • Can terrestrial isopods (Isopoda: Oniscidea) make use of Biodegradable Plastics?
    Applied Soil Ecology, 2014
    Co-Authors: Camila Timm Wood, Martin Zimmer
    Abstract:

    Biodegradable Plastics more and more replace conventional Plastics, because they are considered environmentally friendly. Soil macro-invertebrates have been demonstrated to consume some of these Biodegradable Plastics, but studies usually do not go beyond notice of consumption and possible short-term ecotoxicological effects on organisms. This study uses the terrestrial isopod Porcellio scaber as a soil detritivore model and three Biodegradable Plastics (starch-, cellulose- and poly(3-hydroxybutyrate) (PHB)-based films) to evaluate both the contribution of isopods to the disintegration of Biodegradable Plastics and the effects of plastic-feeding on isopod ecology. Consumption rate of starch-based plastic was similar to that of leaf litter (mainly beech) and on average higher than those of the other two plastic types. Digestibility, however, was highest for cellulose-based plastic. HPLC results show that isopods break down starch-based plastic into maltose and glucose, and cellulose-based plastic into cellobiose. No glucose was present in feces of isopods having fed cellulose-based plastic, either for inability of breaking down cellobiose into glucose, or due to a rapid uptake of the glucose by isopods. Growth rates were negative, but not significantly different from zero, for all food sources; cellulose-based plastic caused the highest biomass loss to isopods. Toughness of starch-based plastic diminished over time when litter and/or isopods were present. Cellulose-based plastic increased in toughness over the disintegration experiment, possibly affecting its consumption by isopods. Overall, isopods increased the disintegration rates of starch- and cellulose-based Plastics, but no PHB film was consumed, and its disintegration rate was low. We conclude that starch-based plastic is comparable to a natural low-quality food source (e.g., beech litter), and isopods would probably consume starch- and cellulose-based Plastics in the field.

  • Can terrestrial isopods (Isopoda: Oniscidea) make use of Biodegradable Plastics?
    Applied Soil Ecology, 2014
    Co-Authors: Camila Timm Wood, Martin Zimmer
    Abstract:

    Biodegradable Plastics more and more replace conventional Plastics, because they are considered environmentally friendly. Soil macro-invertebrates have been demonstrated to consume some of these Biodegradable Plastics, but studies usually do not go beyond notice of consumption and possible short-term ecotoxicological effects on organisms. This study uses the terrestrial isopod Porcellio scaber as a soil detritivore model and three Biodegradable Plastics (starch-, cellulose- and poly(3-hydroxybutyrate) (PHB)-based films) to evaluate both the contribution of isopods to the disintegration of Biodegradable Plastics and the effects of plastic-feeding on isopod ecology. Consumption rate of starch-based plastic was similar to that of leaf litter (mainly beech) and on average higher than those of the other two plastic types. Digestibility, however, was highest for cellulose-based plastic. HPLC results show that isopods break down starch-based plastic into maltose and glucose, and cellulose-based plastic into cellobiose. No glucose was present in feces of isopods having fed cellulose-based plastic, either for inability of breaking down cellobiose into glucose, or due to a rapid uptake of the glucose by isopods. Growth rates were negative, but not significantly different from zero, for all food sources; cellulose-based plastic caused the highest biomass loss to isopods. Toughness of starch-based plastic diminished over time when litter and/or isopods were present. Cellulose-based plastic increased in toughness over the disintegration experiment, possibly affecting its consumption by isopods. Overall, isopods increased the disintegration rates of starch- and cellulose-based Plastics, but no PHB film was consumed, and its disintegration rate was low. We conclude that starch-based plastic is comparable to a natural low-quality food source (e.g., beech litter), and isopods would probably consume starch- and cellulose-based Plastics in the field. © 2014 Elsevier B.V.

Camila Timm Wood - One of the best experts on this subject based on the ideXlab platform.

  • Can terrestrial isopods (Isopoda: Oniscidea) make use of Biodegradable Plastics?
    Applied Soil Ecology, 2014
    Co-Authors: Camila Timm Wood, Martin Zimmer
    Abstract:

    Biodegradable Plastics more and more replace conventional Plastics, because they are considered environmentally friendly. Soil macro-invertebrates have been demonstrated to consume some of these Biodegradable Plastics, but studies usually do not go beyond notice of consumption and possible short-term ecotoxicological effects on organisms. This study uses the terrestrial isopod Porcellio scaber as a soil detritivore model and three Biodegradable Plastics (starch-, cellulose- and poly(3-hydroxybutyrate) (PHB)-based films) to evaluate both the contribution of isopods to the disintegration of Biodegradable Plastics and the effects of plastic-feeding on isopod ecology. Consumption rate of starch-based plastic was similar to that of leaf litter (mainly beech) and on average higher than those of the other two plastic types. Digestibility, however, was highest for cellulose-based plastic. HPLC results show that isopods break down starch-based plastic into maltose and glucose, and cellulose-based plastic into cellobiose. No glucose was present in feces of isopods having fed cellulose-based plastic, either for inability of breaking down cellobiose into glucose, or due to a rapid uptake of the glucose by isopods. Growth rates were negative, but not significantly different from zero, for all food sources; cellulose-based plastic caused the highest biomass loss to isopods. Toughness of starch-based plastic diminished over time when litter and/or isopods were present. Cellulose-based plastic increased in toughness over the disintegration experiment, possibly affecting its consumption by isopods. Overall, isopods increased the disintegration rates of starch- and cellulose-based Plastics, but no PHB film was consumed, and its disintegration rate was low. We conclude that starch-based plastic is comparable to a natural low-quality food source (e.g., beech litter), and isopods would probably consume starch- and cellulose-based Plastics in the field.

  • Can terrestrial isopods (Isopoda: Oniscidea) make use of Biodegradable Plastics?
    Applied Soil Ecology, 2014
    Co-Authors: Camila Timm Wood, Martin Zimmer
    Abstract:

    Biodegradable Plastics more and more replace conventional Plastics, because they are considered environmentally friendly. Soil macro-invertebrates have been demonstrated to consume some of these Biodegradable Plastics, but studies usually do not go beyond notice of consumption and possible short-term ecotoxicological effects on organisms. This study uses the terrestrial isopod Porcellio scaber as a soil detritivore model and three Biodegradable Plastics (starch-, cellulose- and poly(3-hydroxybutyrate) (PHB)-based films) to evaluate both the contribution of isopods to the disintegration of Biodegradable Plastics and the effects of plastic-feeding on isopod ecology. Consumption rate of starch-based plastic was similar to that of leaf litter (mainly beech) and on average higher than those of the other two plastic types. Digestibility, however, was highest for cellulose-based plastic. HPLC results show that isopods break down starch-based plastic into maltose and glucose, and cellulose-based plastic into cellobiose. No glucose was present in feces of isopods having fed cellulose-based plastic, either for inability of breaking down cellobiose into glucose, or due to a rapid uptake of the glucose by isopods. Growth rates were negative, but not significantly different from zero, for all food sources; cellulose-based plastic caused the highest biomass loss to isopods. Toughness of starch-based plastic diminished over time when litter and/or isopods were present. Cellulose-based plastic increased in toughness over the disintegration experiment, possibly affecting its consumption by isopods. Overall, isopods increased the disintegration rates of starch- and cellulose-based Plastics, but no PHB film was consumed, and its disintegration rate was low. We conclude that starch-based plastic is comparable to a natural low-quality food source (e.g., beech litter), and isopods would probably consume starch- and cellulose-based Plastics in the field. © 2014 Elsevier B.V.

Sandeep Narayan Mudliar - One of the best experts on this subject based on the ideXlab platform.

  • activated sludge is a potential source for production of Biodegradable Plastics from wastewater
    Environmental Technology, 2005
    Co-Authors: Anshuman Khardenavis, M.s. Kumar, Prabal K. Guha, Sandeep Narayan Mudliar, Tapan Chakrabarti
    Abstract:

    Increased utilization of synthetic Plastics caused severe environmental pollution due to their non-Biodegradable nature. In the search for environmentally friendly materials to substitute for conventional Plastics, different Biodegradable Plastics have been developed by microbial fermentations. However, limitations of these materials still exist due to high cost. This study aims at minimization of cost for the production of Biodegradable Plastics P(3HB) and minimization of environmental pollution. The waste biological sludge generated at wastewater treatment plants is used for the production of P(3HB) and wastewater is used as carbon source. Activated sludge was induced by controlling the carbon : nitrogen ratio to accumulate storage polymer. Initially polymer accumulation was studied by using different carbon and nitrogen sources. Maximum accumulation of polymer was observed with carbon source acetic acid and diammonium hydrogen phosphate (DAHP) as nitrogen source. Further studies were carried out to opt...

  • Activated sludge is a potential source for production of Biodegradable Plastics from wastewater
    Environmental technology, 2005
    Co-Authors: Anshuman Khardenavis, M.s. Kumar, Prabal K. Guha, Sandeep Narayan Mudliar, Tapan Chakrabarti
    Abstract:

    Increased utilization of synthetic Plastics caused severe environmental pollution due to their non-Biodegradable nature. In the search for environmentally friendly materials to substitute for conventional Plastics, different Biodegradable Plastics have been developed by microbial fermentations. However, limitations of these materials still exist due to high cost. This study aims at minimization of cost for the production of Biodegradable Plastics P(3HB) and minimization of environmental pollution. The waste biological sludge generated at wastewater treatment plants is used for the production of P(3HB) and wastewater is used as carbon source. Activated sludge was induced by controlling the carbon: nitrogen ratio to accumulate storage polymer. Initially polymer accumulation was studied by using different carbon and nitrogen sources. Maximum accumulation of polymer was observed with carbon source acetic acid and diammonium hydrogen phosphate (DAHP) as nitrogen source. Further studies were carried out to optimize the carbon: nitrogen ratios using acetic add and DAHP. A maximum of 65.84% (w/w) P(3HB) production was obtained at C/N ratio of 50 within 96 hours of incubation. © Selper Ltd, 2005.

  • production of Biodegradable Plastics from activated sludge generated from a food processing industrial wastewater treatment plant
    Bioresource Technology, 2004
    Co-Authors: Suresh M Kumar, Sandeep Narayan Mudliar, Krishna Reddy, Tapan Chakrabarti
    Abstract:

    Most of the excess sludge from a wastewater treatment plant (60%) is disposed by landfill. As a resource utilization of excess sludge, the production of Biodegradable Plastics using the sludge has been proposed. Storage polymers in bacterial cells can be extracted and used as Biodegradable Plastics. However, widespread applications have been limited by high production cost. In the present study, activated sludge bacteria in a conventional wastewater treatment system were induced, by controlling the carbon: nitrogen ratio to accumulate storage polymers. Polymer yield increased to a maximum 33% of biomass (w/w) when the C/N ratio was increased from 24 to 144, where as specific growth yield decreased with increasing C/N ratio. The conditions which are required for the maximum polymer accumulation were optimized and are discussed.

  • Production of Biodegradable Plastics from activated sludge generated from a food processing industrial wastewater treatment plant
    Bioresource Technology, 2004
    Co-Authors: M. Suresh Kumar, K. M.k. Reddy, Sandeep Narayan Mudliar, Tapan Chakrabarti
    Abstract:

    Most of the excess sludge from a wastewater treatment plant (60%) is disposed by landfill. As a resource utilization of excess sludge, the production of Biodegradable Plastics using the sludge has been proposed. Storage polymers in bacterial cells can be extracted and used as Biodegradable Plastics. However, widespread applications have been limited by high production cost. In the present study, activated sludge bacteria in a conventional wastewater treatment system were induced, by controlling the carbon: nitrogen ratio to accumulate storage polymers. Polymer yield increased to a maximum 33% of biomass (w/w) when the C/N ratio was increased from 24 to 144, where as specific growth yield decreased with increasing C/N ratio. The conditions which are required for the maximum polymer accumulation were optimized and are discussed. © 2004 Elsevier Ltd. All rights reserved.

William M. Doane - One of the best experts on this subject based on the ideXlab platform.

  • Biodegradable Plastics
    Journal of Polymer Materials, 1994
    Co-Authors: William M. Doane
    Abstract:

    Biodegradable Plastics based on natural polymers are\nnow being produced to replace nonBiodegradable Plastics\nin several applications. Plastic articles that are used\none time and then rapidly disposed of are targeted as\nthe primary market areas. Biodegradable foams, films\nand molded articles for use as disposable plates and\ncutlery, shopping and compost bags, packaging\ncontainers and foams, and mulch films have been\nintroduced during the last few years. Starch has\nreceived the greatest attention as a biopolymer-from\nwhich to produce Biodegradable Plastics. Also, starch\nor sugar, is being fermented either directly into\nBiodegradable polyesters or into hydroxy acids which\nare subsequently polymerized into Biodegradable\npolyesters.

  • USDA Research on Starch‐Based Biodegradable Plastics
    Starch ‐ Stärke, 1992
    Co-Authors: William M. Doane
    Abstract:

    Research on starch-based Biodegradable Plastics began in the 1970's and continues today at the National Center for Agricultural Utilization Research (NCAUR) in Peoria, IL. Technology has been developed for producing extrusion blown films and injection molded articles containing 50% and more of starch. Extrusion processing of compositions containing starch and other natural polymers to provide totally Biodegradable Plastics is being investigated. Starch grafted with thermoplastic side chains is under commercial development to provide injection molded items with a broad range of compositions and properties. The mechanism of biological degradation and the rate and extent of biodegradation of starch containing Plastics in various environments is studied to enhance development and acceptance of Biodegradable Plastics. USDA-Forschung über biologisch abbaubare Kunststoffe auf Stärkebasis. Die Forschung an auf Stärke basierenden Kunststoffen begann in den 70er Jahren und wird heute im National Center for Agricultural Utilization (NCAUR) in Peoria, IL, fortgesetzt. Es wurde eine Technologie zur Herstellung von extrusionsgeblasenen Filmen und spritzgeformten Gegenständen mit mehr als 50% Stärkegehalt entwickelt. Das Extrusionsverfahren mit Zusammensetzungen, die Stärke und andere natürliche Polymere enthalten, um total biologisch abbaubare Kunststoffe zu gewinnen, wird untersucht. Mit thermoplastischen Seitenketten gepfropfte Stärke befindet sich in wirtschaftlicher Entwicklung, um spritzgußgeformte Teile mit einem breiten Bereich an Zusammensetzungen und Eigenschaften zu erhalten. Der Mechanismus des biologischen Abbaues sowie Geschwindigkeit und Ausmaß des Bioabbaues stärkehaltiger Kunststoffe in verschiedenen Umgebungen wird untersucht, um die Entwicklung und die Akzeptanz biologisch abbaubarer Kunststoffe zu fördern.

  • usda research on starch based Biodegradable Plastics
    Starch-starke, 1992
    Co-Authors: William M. Doane
    Abstract:

    Research on starch-based Biodegradable Plastics began in the 1970's and continues today at the National Center for Agricultural Utilization Research (NCAUR) in Peoria, IL. Technology has been developed for producing extrusion blown films and injection molded articles containing 50% and more of starch. Extrusion processing of compositions containing starch and other natural polymers to provide totally Biodegradable Plastics is being investigated. Starch grafted with thermoplastic side chains is under commercial development to provide injection molded items with a broad range of compositions and properties. The mechanism of biological degradation and the rate and extent of biodegradation of starch containing Plastics in various environments is studied to enhance development and acceptance of Biodegradable Plastics.