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David A Mitchell - One of the best experts on this subject based on the ideXlab platform.
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intermittent agitation contributes to uniformity across the bed during Pectinase production by aspergillus niger grown in solid state fermentation in a pilot scale packed bed bioreactor
Biochemical Engineering Journal, 2017Co-Authors: Anelize Terezinha Jung Finkler, Alessandra Biz, Luana Oliveira Pitol, Bruna Schweitzer Medina, Nadia Krieger, Henrique Luithardt, Luiz Fernando De Lima Luz, David A MitchellAbstract:Abstract Solid-state fermentation could be used to produce low-cost Pectinases that could then be used to saccharify pectin in citrus waste biorefineries. Recently, we produced Pectinases in a pilot-scale packed-bed bioreactor, growing Aspergillus niger on a substrate mixture consisting of 27 kg of wheat bran and 3 kg of sugarcane bagasse (dry mass). However, the agglomeration of particles and shrinkage of the bed created preferential flow paths, leading to overheating within the bed and poor uniformity of Pectinase levels at the end of the fermentation. In the current work, we used intermittent agitation as a strategy to minimize agglomeration, comparing one agitation (10 h), three agitations (at 8, 10 and 12 h) and five agitations (every 2 h from 8 to 16 h). The Pectinase activity in the bed was uniform after agitation, but poor uniformity occurred when the bed was left unmixed for more than 10 h. The best regime was that with three agitations: For 15 samples removed from different vertical and horizontal positions of the bed at 20 h, the average Pectinase activity was 22 U g−1, with a sample standard deviation of 2 U g−1. We conclude that the use of intermittently-mixed packed-bed bioreactors is a promising strategy for producing Pectinases in solid-state fermentation.
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production of Pectinases by solid state fermentation of a mixture of citrus waste and sugarcane bagasse in a pilot scale packed bed bioreactor
Biochemical Engineering Journal, 2016Co-Authors: Alessandra Biz, Anelize Terezinha Jung Finkler, Luana Oliveira Pitol, Bruna Schweitzer Medina, Nadia Krieger, David A MitchellAbstract:Abstract Pectinases can be used in citrus waste biorefineries to hydrolyze the pectin in citrus pulp to produce d -galacturonic acid, a potential platform chemical. Solid-state fermentation has the potential to produce low-cost Pectinases for such biorefineries, but it is difficult to control the process at large scales. In the current work, Aspergillus oryzae was cultivated in a pilot-scale packed-bed bioreactor, on 15 kg of a substrate containing 51.6% citrus pulp and 48.4% sugarcane bagasse (w/w, dry basis). The sugarcane bagasse gave a high bed porosity and ensured a stable bed structure, avoiding problems of bed shrinkage and the formation of compact agglomerates within the bed. As a result, bed temperatures were controlled to within 1 °C of the inlet air temperature and Pectinase yields of 33–41 U g −1 were obtained across the bed. When the fermented solids were dried and added directly to a pectin solution, they gave a profile for the release of d -galacturonic acid similar to that obtained with a commercial Pectinase. These results show the potential for using solid-state fermentation to produce Pectinases in a citrus waste biorefinery, with subsequent direct addition of the fermented solids to produce d -galacturonic acid from the pectin contained in the citrus pulp.
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production of Pectinases by solid state fermentation in a pilot scale packed bed bioreactor
Chemical Engineering Journal, 2016Co-Authors: Luana Oliveira Pitol, Alessandra Biz, Nadia Krieger, Edgar Mallmann, David A MitchellAbstract:Abstract Solid-state fermentation can be used to produce Pectinases using agro-industrial byproducts. However, heat and mass transfer limitations make it difficult to control the temperature within the bioreactor, especially at large scale, so reliable scale-up strategies are essential. In the current work, we scaled up the production of Pectinases in packed-bed bioreactors, from 12 g to 30 kg of dry substrate, the biggest scale yet reported for Pectinase production. When compaction occurred, bed temperatures up to 47 °C were recorded and the Pectinase activity in different regions of the bed at 26 h varied from 11 to 28 × 10 3 U kg −1 . When compaction was avoided, the maximum bed temperature was 32 °C and the Pectinase activity at 26 h varied from 17 to 20 × 10 3 U kg −1 . The best result was obtained with a 40-cm high bed containing 27 kg of wheat bran and 3 kg of sugarcane bagasse, with switching of the temperature of the saturated inlet air between 24 °C and 32 °C. Under these conditions, the maximum productivity was 1840 U kg −1 h −1 at 10 h. We propose that the process can be scaled up to production scale by maintaining the same bed height and operational strategy, while increasing the width of the bed to several meters. If the superficial velocity of the air is maintained constant at 0.1 m s −1 , then the performance at scales involving several tonnes of solid substrate should be similar to that obtained in pilot-scale bioreactor in the current study.
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Pectinase activity determination an early deceleration in the release of reducing sugars throws a spanner in the works
PLOS ONE, 2014Co-Authors: Alessandra Biz, Nadia Krieger, Fernanda Cardoso Farias, Francine Aline Motter, Diogo Henrique De Paula, Peter Richard, David A MitchellAbstract:Recently, it has been suggested that Pectinases could be used to hydrolyze pectin in biorefineries based on pectin-rich agro-industrial wastes. However, for this to be viable, the cost of their production would need to be lowered significantly. In fact, over the last few decades, there have been many attempts to improve Pectinase production by existing strains or to screen for new strains from environmental isolates. In these studies, it is necessary to measure Pectinase activities. Many researchers use single-time-point assays that involve incubation of pectinolytic extracts with pectic substrates for a fixed time, followed by determination of the liberated reducing sugars. However, different researchers use quite different conditions for this assay. Furthermore, no attention has been given to the reaction profile during the assay. In the current work, we show, for the first time, that a significant deceleration of the rate of liberation of reducing sugars occurs over the first ten minutes of the reaction. As a consequence, the incubation time used in a single-time-point assay has a large effect on the value obtained for the activity. In fact, we demonstrate that, depending on the particular combination of incubation time, pectin concentration and reaction temperature, the same extract could be reported to have activities that differ by an order of magnitude. In addition, we show that the relative activities obtained with polygalacturonic acid do not correlate with those obtained with pectin. We conclude that it is currently impossible to make meaningful comparisons between Pectinase activities reported in the literature by workers who have used different assay conditions. Therefore there is an urgent need for the development of a standardized assay for evaluating the saccharification potential of Pectinase complexes.
Alessandra Biz - One of the best experts on this subject based on the ideXlab platform.
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intermittent agitation contributes to uniformity across the bed during Pectinase production by aspergillus niger grown in solid state fermentation in a pilot scale packed bed bioreactor
Biochemical Engineering Journal, 2017Co-Authors: Anelize Terezinha Jung Finkler, Alessandra Biz, Luana Oliveira Pitol, Bruna Schweitzer Medina, Nadia Krieger, Henrique Luithardt, Luiz Fernando De Lima Luz, David A MitchellAbstract:Abstract Solid-state fermentation could be used to produce low-cost Pectinases that could then be used to saccharify pectin in citrus waste biorefineries. Recently, we produced Pectinases in a pilot-scale packed-bed bioreactor, growing Aspergillus niger on a substrate mixture consisting of 27 kg of wheat bran and 3 kg of sugarcane bagasse (dry mass). However, the agglomeration of particles and shrinkage of the bed created preferential flow paths, leading to overheating within the bed and poor uniformity of Pectinase levels at the end of the fermentation. In the current work, we used intermittent agitation as a strategy to minimize agglomeration, comparing one agitation (10 h), three agitations (at 8, 10 and 12 h) and five agitations (every 2 h from 8 to 16 h). The Pectinase activity in the bed was uniform after agitation, but poor uniformity occurred when the bed was left unmixed for more than 10 h. The best regime was that with three agitations: For 15 samples removed from different vertical and horizontal positions of the bed at 20 h, the average Pectinase activity was 22 U g−1, with a sample standard deviation of 2 U g−1. We conclude that the use of intermittently-mixed packed-bed bioreactors is a promising strategy for producing Pectinases in solid-state fermentation.
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production of Pectinases by solid state fermentation of a mixture of citrus waste and sugarcane bagasse in a pilot scale packed bed bioreactor
Biochemical Engineering Journal, 2016Co-Authors: Alessandra Biz, Anelize Terezinha Jung Finkler, Luana Oliveira Pitol, Bruna Schweitzer Medina, Nadia Krieger, David A MitchellAbstract:Abstract Pectinases can be used in citrus waste biorefineries to hydrolyze the pectin in citrus pulp to produce d -galacturonic acid, a potential platform chemical. Solid-state fermentation has the potential to produce low-cost Pectinases for such biorefineries, but it is difficult to control the process at large scales. In the current work, Aspergillus oryzae was cultivated in a pilot-scale packed-bed bioreactor, on 15 kg of a substrate containing 51.6% citrus pulp and 48.4% sugarcane bagasse (w/w, dry basis). The sugarcane bagasse gave a high bed porosity and ensured a stable bed structure, avoiding problems of bed shrinkage and the formation of compact agglomerates within the bed. As a result, bed temperatures were controlled to within 1 °C of the inlet air temperature and Pectinase yields of 33–41 U g −1 were obtained across the bed. When the fermented solids were dried and added directly to a pectin solution, they gave a profile for the release of d -galacturonic acid similar to that obtained with a commercial Pectinase. These results show the potential for using solid-state fermentation to produce Pectinases in a citrus waste biorefinery, with subsequent direct addition of the fermented solids to produce d -galacturonic acid from the pectin contained in the citrus pulp.
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production of Pectinases by solid state fermentation in a pilot scale packed bed bioreactor
Chemical Engineering Journal, 2016Co-Authors: Luana Oliveira Pitol, Alessandra Biz, Nadia Krieger, Edgar Mallmann, David A MitchellAbstract:Abstract Solid-state fermentation can be used to produce Pectinases using agro-industrial byproducts. However, heat and mass transfer limitations make it difficult to control the temperature within the bioreactor, especially at large scale, so reliable scale-up strategies are essential. In the current work, we scaled up the production of Pectinases in packed-bed bioreactors, from 12 g to 30 kg of dry substrate, the biggest scale yet reported for Pectinase production. When compaction occurred, bed temperatures up to 47 °C were recorded and the Pectinase activity in different regions of the bed at 26 h varied from 11 to 28 × 10 3 U kg −1 . When compaction was avoided, the maximum bed temperature was 32 °C and the Pectinase activity at 26 h varied from 17 to 20 × 10 3 U kg −1 . The best result was obtained with a 40-cm high bed containing 27 kg of wheat bran and 3 kg of sugarcane bagasse, with switching of the temperature of the saturated inlet air between 24 °C and 32 °C. Under these conditions, the maximum productivity was 1840 U kg −1 h −1 at 10 h. We propose that the process can be scaled up to production scale by maintaining the same bed height and operational strategy, while increasing the width of the bed to several meters. If the superficial velocity of the air is maintained constant at 0.1 m s −1 , then the performance at scales involving several tonnes of solid substrate should be similar to that obtained in pilot-scale bioreactor in the current study.
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Pectinase activity determination an early deceleration in the release of reducing sugars throws a spanner in the works
PLOS ONE, 2014Co-Authors: Alessandra Biz, Nadia Krieger, Fernanda Cardoso Farias, Francine Aline Motter, Diogo Henrique De Paula, Peter Richard, David A MitchellAbstract:Recently, it has been suggested that Pectinases could be used to hydrolyze pectin in biorefineries based on pectin-rich agro-industrial wastes. However, for this to be viable, the cost of their production would need to be lowered significantly. In fact, over the last few decades, there have been many attempts to improve Pectinase production by existing strains or to screen for new strains from environmental isolates. In these studies, it is necessary to measure Pectinase activities. Many researchers use single-time-point assays that involve incubation of pectinolytic extracts with pectic substrates for a fixed time, followed by determination of the liberated reducing sugars. However, different researchers use quite different conditions for this assay. Furthermore, no attention has been given to the reaction profile during the assay. In the current work, we show, for the first time, that a significant deceleration of the rate of liberation of reducing sugars occurs over the first ten minutes of the reaction. As a consequence, the incubation time used in a single-time-point assay has a large effect on the value obtained for the activity. In fact, we demonstrate that, depending on the particular combination of incubation time, pectin concentration and reaction temperature, the same extract could be reported to have activities that differ by an order of magnitude. In addition, we show that the relative activities obtained with polygalacturonic acid do not correlate with those obtained with pectin. We conclude that it is currently impossible to make meaningful comparisons between Pectinase activities reported in the literature by workers who have used different assay conditions. Therefore there is an urgent need for the development of a standardized assay for evaluating the saccharification potential of Pectinase complexes.
Nadia Krieger - One of the best experts on this subject based on the ideXlab platform.
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intermittent agitation contributes to uniformity across the bed during Pectinase production by aspergillus niger grown in solid state fermentation in a pilot scale packed bed bioreactor
Biochemical Engineering Journal, 2017Co-Authors: Anelize Terezinha Jung Finkler, Alessandra Biz, Luana Oliveira Pitol, Bruna Schweitzer Medina, Nadia Krieger, Henrique Luithardt, Luiz Fernando De Lima Luz, David A MitchellAbstract:Abstract Solid-state fermentation could be used to produce low-cost Pectinases that could then be used to saccharify pectin in citrus waste biorefineries. Recently, we produced Pectinases in a pilot-scale packed-bed bioreactor, growing Aspergillus niger on a substrate mixture consisting of 27 kg of wheat bran and 3 kg of sugarcane bagasse (dry mass). However, the agglomeration of particles and shrinkage of the bed created preferential flow paths, leading to overheating within the bed and poor uniformity of Pectinase levels at the end of the fermentation. In the current work, we used intermittent agitation as a strategy to minimize agglomeration, comparing one agitation (10 h), three agitations (at 8, 10 and 12 h) and five agitations (every 2 h from 8 to 16 h). The Pectinase activity in the bed was uniform after agitation, but poor uniformity occurred when the bed was left unmixed for more than 10 h. The best regime was that with three agitations: For 15 samples removed from different vertical and horizontal positions of the bed at 20 h, the average Pectinase activity was 22 U g−1, with a sample standard deviation of 2 U g−1. We conclude that the use of intermittently-mixed packed-bed bioreactors is a promising strategy for producing Pectinases in solid-state fermentation.
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production of Pectinases by solid state fermentation of a mixture of citrus waste and sugarcane bagasse in a pilot scale packed bed bioreactor
Biochemical Engineering Journal, 2016Co-Authors: Alessandra Biz, Anelize Terezinha Jung Finkler, Luana Oliveira Pitol, Bruna Schweitzer Medina, Nadia Krieger, David A MitchellAbstract:Abstract Pectinases can be used in citrus waste biorefineries to hydrolyze the pectin in citrus pulp to produce d -galacturonic acid, a potential platform chemical. Solid-state fermentation has the potential to produce low-cost Pectinases for such biorefineries, but it is difficult to control the process at large scales. In the current work, Aspergillus oryzae was cultivated in a pilot-scale packed-bed bioreactor, on 15 kg of a substrate containing 51.6% citrus pulp and 48.4% sugarcane bagasse (w/w, dry basis). The sugarcane bagasse gave a high bed porosity and ensured a stable bed structure, avoiding problems of bed shrinkage and the formation of compact agglomerates within the bed. As a result, bed temperatures were controlled to within 1 °C of the inlet air temperature and Pectinase yields of 33–41 U g −1 were obtained across the bed. When the fermented solids were dried and added directly to a pectin solution, they gave a profile for the release of d -galacturonic acid similar to that obtained with a commercial Pectinase. These results show the potential for using solid-state fermentation to produce Pectinases in a citrus waste biorefinery, with subsequent direct addition of the fermented solids to produce d -galacturonic acid from the pectin contained in the citrus pulp.
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production of Pectinases by solid state fermentation in a pilot scale packed bed bioreactor
Chemical Engineering Journal, 2016Co-Authors: Luana Oliveira Pitol, Alessandra Biz, Nadia Krieger, Edgar Mallmann, David A MitchellAbstract:Abstract Solid-state fermentation can be used to produce Pectinases using agro-industrial byproducts. However, heat and mass transfer limitations make it difficult to control the temperature within the bioreactor, especially at large scale, so reliable scale-up strategies are essential. In the current work, we scaled up the production of Pectinases in packed-bed bioreactors, from 12 g to 30 kg of dry substrate, the biggest scale yet reported for Pectinase production. When compaction occurred, bed temperatures up to 47 °C were recorded and the Pectinase activity in different regions of the bed at 26 h varied from 11 to 28 × 10 3 U kg −1 . When compaction was avoided, the maximum bed temperature was 32 °C and the Pectinase activity at 26 h varied from 17 to 20 × 10 3 U kg −1 . The best result was obtained with a 40-cm high bed containing 27 kg of wheat bran and 3 kg of sugarcane bagasse, with switching of the temperature of the saturated inlet air between 24 °C and 32 °C. Under these conditions, the maximum productivity was 1840 U kg −1 h −1 at 10 h. We propose that the process can be scaled up to production scale by maintaining the same bed height and operational strategy, while increasing the width of the bed to several meters. If the superficial velocity of the air is maintained constant at 0.1 m s −1 , then the performance at scales involving several tonnes of solid substrate should be similar to that obtained in pilot-scale bioreactor in the current study.
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Pectinase activity determination an early deceleration in the release of reducing sugars throws a spanner in the works
PLOS ONE, 2014Co-Authors: Alessandra Biz, Nadia Krieger, Fernanda Cardoso Farias, Francine Aline Motter, Diogo Henrique De Paula, Peter Richard, David A MitchellAbstract:Recently, it has been suggested that Pectinases could be used to hydrolyze pectin in biorefineries based on pectin-rich agro-industrial wastes. However, for this to be viable, the cost of their production would need to be lowered significantly. In fact, over the last few decades, there have been many attempts to improve Pectinase production by existing strains or to screen for new strains from environmental isolates. In these studies, it is necessary to measure Pectinase activities. Many researchers use single-time-point assays that involve incubation of pectinolytic extracts with pectic substrates for a fixed time, followed by determination of the liberated reducing sugars. However, different researchers use quite different conditions for this assay. Furthermore, no attention has been given to the reaction profile during the assay. In the current work, we show, for the first time, that a significant deceleration of the rate of liberation of reducing sugars occurs over the first ten minutes of the reaction. As a consequence, the incubation time used in a single-time-point assay has a large effect on the value obtained for the activity. In fact, we demonstrate that, depending on the particular combination of incubation time, pectin concentration and reaction temperature, the same extract could be reported to have activities that differ by an order of magnitude. In addition, we show that the relative activities obtained with polygalacturonic acid do not correlate with those obtained with pectin. We conclude that it is currently impossible to make meaningful comparisons between Pectinase activities reported in the literature by workers who have used different assay conditions. Therefore there is an urgent need for the development of a standardized assay for evaluating the saccharification potential of Pectinase complexes.
Luana Oliveira Pitol - One of the best experts on this subject based on the ideXlab platform.
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intermittent agitation contributes to uniformity across the bed during Pectinase production by aspergillus niger grown in solid state fermentation in a pilot scale packed bed bioreactor
Biochemical Engineering Journal, 2017Co-Authors: Anelize Terezinha Jung Finkler, Alessandra Biz, Luana Oliveira Pitol, Bruna Schweitzer Medina, Nadia Krieger, Henrique Luithardt, Luiz Fernando De Lima Luz, David A MitchellAbstract:Abstract Solid-state fermentation could be used to produce low-cost Pectinases that could then be used to saccharify pectin in citrus waste biorefineries. Recently, we produced Pectinases in a pilot-scale packed-bed bioreactor, growing Aspergillus niger on a substrate mixture consisting of 27 kg of wheat bran and 3 kg of sugarcane bagasse (dry mass). However, the agglomeration of particles and shrinkage of the bed created preferential flow paths, leading to overheating within the bed and poor uniformity of Pectinase levels at the end of the fermentation. In the current work, we used intermittent agitation as a strategy to minimize agglomeration, comparing one agitation (10 h), three agitations (at 8, 10 and 12 h) and five agitations (every 2 h from 8 to 16 h). The Pectinase activity in the bed was uniform after agitation, but poor uniformity occurred when the bed was left unmixed for more than 10 h. The best regime was that with three agitations: For 15 samples removed from different vertical and horizontal positions of the bed at 20 h, the average Pectinase activity was 22 U g−1, with a sample standard deviation of 2 U g−1. We conclude that the use of intermittently-mixed packed-bed bioreactors is a promising strategy for producing Pectinases in solid-state fermentation.
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production of Pectinases by solid state fermentation of a mixture of citrus waste and sugarcane bagasse in a pilot scale packed bed bioreactor
Biochemical Engineering Journal, 2016Co-Authors: Alessandra Biz, Anelize Terezinha Jung Finkler, Luana Oliveira Pitol, Bruna Schweitzer Medina, Nadia Krieger, David A MitchellAbstract:Abstract Pectinases can be used in citrus waste biorefineries to hydrolyze the pectin in citrus pulp to produce d -galacturonic acid, a potential platform chemical. Solid-state fermentation has the potential to produce low-cost Pectinases for such biorefineries, but it is difficult to control the process at large scales. In the current work, Aspergillus oryzae was cultivated in a pilot-scale packed-bed bioreactor, on 15 kg of a substrate containing 51.6% citrus pulp and 48.4% sugarcane bagasse (w/w, dry basis). The sugarcane bagasse gave a high bed porosity and ensured a stable bed structure, avoiding problems of bed shrinkage and the formation of compact agglomerates within the bed. As a result, bed temperatures were controlled to within 1 °C of the inlet air temperature and Pectinase yields of 33–41 U g −1 were obtained across the bed. When the fermented solids were dried and added directly to a pectin solution, they gave a profile for the release of d -galacturonic acid similar to that obtained with a commercial Pectinase. These results show the potential for using solid-state fermentation to produce Pectinases in a citrus waste biorefinery, with subsequent direct addition of the fermented solids to produce d -galacturonic acid from the pectin contained in the citrus pulp.
-
production of Pectinases by solid state fermentation in a pilot scale packed bed bioreactor
Chemical Engineering Journal, 2016Co-Authors: Luana Oliveira Pitol, Alessandra Biz, Nadia Krieger, Edgar Mallmann, David A MitchellAbstract:Abstract Solid-state fermentation can be used to produce Pectinases using agro-industrial byproducts. However, heat and mass transfer limitations make it difficult to control the temperature within the bioreactor, especially at large scale, so reliable scale-up strategies are essential. In the current work, we scaled up the production of Pectinases in packed-bed bioreactors, from 12 g to 30 kg of dry substrate, the biggest scale yet reported for Pectinase production. When compaction occurred, bed temperatures up to 47 °C were recorded and the Pectinase activity in different regions of the bed at 26 h varied from 11 to 28 × 10 3 U kg −1 . When compaction was avoided, the maximum bed temperature was 32 °C and the Pectinase activity at 26 h varied from 17 to 20 × 10 3 U kg −1 . The best result was obtained with a 40-cm high bed containing 27 kg of wheat bran and 3 kg of sugarcane bagasse, with switching of the temperature of the saturated inlet air between 24 °C and 32 °C. Under these conditions, the maximum productivity was 1840 U kg −1 h −1 at 10 h. We propose that the process can be scaled up to production scale by maintaining the same bed height and operational strategy, while increasing the width of the bed to several meters. If the superficial velocity of the air is maintained constant at 0.1 m s −1 , then the performance at scales involving several tonnes of solid substrate should be similar to that obtained in pilot-scale bioreactor in the current study.
A Dayanand - One of the best experts on this subject based on the ideXlab platform.
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optimization of process for the production of fungal Pectinases from deseeded sunflower head in submerged and solid state conditions
Bioresource Technology, 2006Co-Authors: Sarvamangala R Patil, A DayanandAbstract:Abstract Pectinase production studies were carried out in submerged and solid-state conditions from deseeded sunflower head employing Aspergillus niger . The two potential strains of A. niger , DMF 27 for submerged and DMF 45 for solid-state were isolated by multi-step screening technique based on coefficient of pectolysis and capability of Pectinase production. Process variables such as size of inoculum, pH, temperature, particle size and moisture content were optimized with an aim to achieve the maximum production of Pectinases. The increased level of Pectinase production was recorded at pH 5.0 and temperature 34 °C in submerged and solid-state conditions. The optimum inoculum size was 1 × 10 5 ml −1 for submerged and 1 × 10 7 g −1 for solid-state conditions. Five hundred micrometer particle size and 65% moisture content of the substrate were optimum for the maximum production of Pectinases in solid-state condition. Under optimum conditions, maximum production of exo-Pectinase was 34.2 U/g in SSF and endo-Pectinase was 12.6 U/ml in SmF.
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production of Pectinase from deseeded sunflower head by aspergillus niger in submerged and solid state conditions
Bioresource Technology, 2006Co-Authors: Sarvamangala R Patil, A DayanandAbstract:Studies were carried out on the production of Pectinases using deseeded sunflower head by Aspergillus niger DMF 27 and DMF 45 in submerged fermentation (SmF) and solid-state fermentation (SSF). Higher titres of endo- and exo-Pectinases were observed when medium was supplemented with carbon (4% glucose for SmF and 6% sucrose for SSF) and nitrogen (ammonium sulphate, 0.3% for both SmF and SSF) sources. Green gram husk proved to be relatively a better supplement to attain higher yield of endo-Pectinase (11.7 U/g) and exo-Pectinase (30.0 U/g) in solid-state conditions. Maximum production of endo-Pectinase (19.8 U/g) and exo-Pectinase (45.9 U/g) by DMF 45 were recorded in SSF when compared to endo-Pectinase (18.9 U/ml) and exo-Pectinase (30.3 U/ml) by DMF 27 in SmF under optimum process conditions.