The Experts below are selected from a list of 35310 Experts worldwide ranked by ideXlab platform

João Carlos Monteiro De Carvalho - One of the best experts on this subject based on the ideXlab platform.

  • Application of Physicochemical Treatment Allows Reutilization of Arthrospira platensis Exhausted Medium : An Investigation of Reusing Medium in Arthrospira platensis Cultivation.
    Applied biochemistry and biotechnology, 2018
    Co-Authors: Lauris Del Carmen Mejia-da-silva, Marcelo Chuei Matsudo, Ana Lucia Morocho-jacome, João Carlos Monteiro De Carvalho
    Abstract:

    Since cultivations of Arthrospira platensis have a high water demand, it is necessary to develop treatment methods for reusing the exhausted medium that may prevent environmental problems and obtaining useful biomass. The exhausted Schlosser medium obtained from A. platensis batch cultivation in bench-scale mini-tanks was treated by varying Concentrations of different coagulants, ferric chloride (6, 10, and 14 mg L−1) or ferric sulfate (15, 25, and 35 mg L−1) and powdered activated carbon (PAC, 30 and 50 mg L−1). Such treated effluent was restored with NaNO3 and reused in new cultivations of A. platensis performed in Erlenmeyer flasks. Reusing media through the cultivation of A. platensis showed satisfactory results, particularly in the medium treated with ferric chloride and PAC. The Maximum Cell Concentration obtained in the flasks was 1093 mg L−1, which corresponded to the medium treated with ferric chloride (6 mg L−1) and PAC (30 mg L−1). This Cellular growth was higher than in the medium treated with ferric sulfate and PAC, in which values of Maximum Cell Concentration did not exceed 796 mg L−1. The cultures in the media after treatment did not modify the biomass composition. Thus, combined coagulation/adsorption processes, commonly used in water treatment processes, can be efficient and viable for treating exhausted medium of A. platensis, allowing the production of such biomass with the reduction of production cost and saving water.

  • Evaluation of physicochemical treatment conditions for the reuse of a spent growth medium in Arthrospira platensis cultivation
    Algal Research, 2016
    Co-Authors: Ana Lucia Morocho-jacome, Sunao Sato, Guilherme Favaro Mascioli, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract Arthrospira platensis is a microorganism that is produced worldwide. Its industrial cultivation requires a large quantity of alkaline medium with high salinity that could pollute the environment if discharged with no further treatment. The combined effects of the physicochemical processes of flocculation and adsorption were applied to reuse the spent modified Schlosser medium for seven days of A. platensis fed-batch cultivation using urea as nitrogen source. Different Concentrations of both powdered activated carbon and ferric chloride were evaluated at different contact times to remove organic matter and pigments from the spent medium. The efficiency of the process was measured by evaluating the removal of both organic matter and pigments. The best conditions of treatment that maximized the Cell growth were 24.4 mg L− 1 powdered activated carbon, 20.3 mg L− 1 ferric chloride and 30.4 min of contact time. Under such conditions, organic matter removal was 92.3 ± 0.6%, pigment removal was 95.3 ± 0.6% and the Maximum Cell Concentration was (4.89 ± 0.03) × 103 mg L− 1, approximately 135% higher than in the standard medium [(2.09 ± 0.05) × 103 mg L− 1]. This biomass had 36.1 ± 0.6% protein content, which was also higher than those values obtained in the standard medium (25.8 ± 0.9%).

  • arthrospira spirulina platensis cultivation in tubular photobioreactor use of no cost co2 from ethanol fermentation
    Applied Energy, 2012
    Co-Authors: Attilio Converti, Sunao Sato, Livia Seno Ferreira, Mayla Santos Rodrigues, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract The present study aimed at evaluating the production of Arthrospira platensis in tubular photobioreactor using CO2 from ethanol fermentation. The results of these cultivations were compared to those obtained using CO2 from cylinder at different protocols of simultaneous ammonium sulfate and sodium nitrate feeding. Maximum Cell Concentration (Xm), Cell productivity (Px), nitrogen-to-Cell conversion factor (YX/N), and biomass composition (total lipids and proteins) were selected as responses and evaluated by analysis of variance. The source of CO2 did not exert any significant statistical influence on these responses, which means that the flue gas from ethanol fermentation could successfully be used as a carbon source as well as to control the medium pH, thus contributing to reduce the greenhouse effect. The results taken as a whole demonstrated that the best combination of responses mean values (Xm = 4.543 g L−1; Px = 0.460 g L−1 d−1; YX/N = 15.6 g g−1; total lipids = 8.39%; total proteins = 18.7%) was obtained using as nitrogen source a mixture of 25% NaNO3 and 75% (NH4)2SO4, both expressed as nitrogen.

  • influence of ammonium sulphate feeding time on fed batch arthrospira spirulina platensis cultivation and biomass composition with and without ph control
    Bioresource Technology, 2011
    Co-Authors: Mayla Santos Rodrigues, Attilio Converti, Sunao Sato, Livia Seno Ferreira, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract Previous work demonstrated that a mixture of NH4Cl and KNO3 as nitrogen source was beneficial to fed-batch Arthrospira (Spirulina) platensis cultivation, in terms of either lower costs or higher Cell Concentration. On the basis of those results, this study focused on the use of a cheaper nitrogen source mixture, namely (NH4)2SO4 plus NaNO3, varying the ammonium feeding time (T = 7–15 days), either controlling the pH by CO2 addition or not. A. platensis was cultivated in mini-tanks at 30 °C, 156 μmol photons m−2 s−1, and starting Cell Concentration of 400 mg L−1, on a modified Schlosser medium. T = 13 days under pH control were selected as optimum conditions, ensuring the best results in terms of biomass production (Maximum Cell Concentration of 2911 mg L−1, Cell productivity of 179 mg L−1 d−1 and specific growth rate of 0.77 d−1) and satisfactory protein and lipid contents (around 30% each).

  • effects of light intensity and dilution rate on the semicontinuous cultivation of arthrospira spirulina platensis a kinetic monod type approach
    Bioresource Technology, 2011
    Co-Authors: Raquel Pedrosa Bezerra, João Carlos Monteiro De Carvalho, Sunao Sato, Attilio Converti, Patrizia Perego, Erika Yuliana Ortiz Montoya
    Abstract:

    Abstract Semicontinuous cultures were carried out at different dilution rates (D) and light intensities (I) to determine the Maximum productivity of Arthrospira platensis cultivated in helicoidal photobioreactor up to the achievement of pseudo-steady-state conditions. At I = 108 μmol photons m−2 s−1, the semicontinuous regime ensured the highest values of Maximum Cell Concentration (Xm = 5772 ± 113 mg L−1) and productivity (PXS = 1319 ± 25 mg L−1 d−1) at the lowest (D = 0.1 day−1) and the highest (D = 0.3 day−1) dilution rates, respectively. A kinetic model derived from that of Monod was proposed to determine the relationship between the product of light intensity to dilution rate (ID) and the Cell productivity, which were shown to exert a combined influence on this parameter. This result put into evidence that pseudo-steady-state conditions could be modified according to circumstances, conveniently varying one or other of the two independent variables.

Attilio Converti - One of the best experts on this subject based on the ideXlab platform.

  • Fed-Batch Cultivation of Arthrospira platensis Using Carbon Dioxide from Alcoholic Fermentation and Urea as Carbon and Nitrogen Sources
    BioEnergy Research, 2013
    Co-Authors: Raquel Pedrosa Bezerra, Marcelo Chuei Matsudo, Sunao Sato, Attilio Converti, João Carlos M Carvalho
    Abstract:

    To reduce CO2 emissions from alcoholic fermentation, Arthrospira platensis was cultivated in tubular photobioreactor using either urea or nitrate as nitrogen sources at different light intensities (60 μmol m−2 s−1 ≤ I ≤ 240 μmol m−2 s−1). The type of carbon source (pure CO2 or CO2 from fermentation) did not show any appreciable influence on the main cultivation parameters, whereas substitution of nitrate for urea increased the nitrogen-to-Cell conversion factor (YX/N), and the Maximum Cell Concentration (Xm) and productivity (PX) increased with I. As a result, the best performance using gaseous emissions from alcoholic fermentation (Xm = 2,960 ± 35 g m−3, PX = 425 ± 5.9 g m−3 day−1 and YX/N = 15 ± 0.2 g g−1) was obtained at I = 120 μmol m−2 s−1 using urea as nitrogen source. The results obtained in this work demonstrate that the combined use of effluents rich in urea and carbon dioxide could be exploited in large-scale cyanobacteria cultivations to reduce not only the production costs of these photosynthetic microorganisms but also the environmental impact associated to the release of greenhouse emissions.

  • arthrospira spirulina platensis cultivation in tubular photobioreactor use of no cost co2 from ethanol fermentation
    Applied Energy, 2012
    Co-Authors: Attilio Converti, Sunao Sato, Livia Seno Ferreira, Mayla Santos Rodrigues, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract The present study aimed at evaluating the production of Arthrospira platensis in tubular photobioreactor using CO2 from ethanol fermentation. The results of these cultivations were compared to those obtained using CO2 from cylinder at different protocols of simultaneous ammonium sulfate and sodium nitrate feeding. Maximum Cell Concentration (Xm), Cell productivity (Px), nitrogen-to-Cell conversion factor (YX/N), and biomass composition (total lipids and proteins) were selected as responses and evaluated by analysis of variance. The source of CO2 did not exert any significant statistical influence on these responses, which means that the flue gas from ethanol fermentation could successfully be used as a carbon source as well as to control the medium pH, thus contributing to reduce the greenhouse effect. The results taken as a whole demonstrated that the best combination of responses mean values (Xm = 4.543 g L−1; Px = 0.460 g L−1 d−1; YX/N = 15.6 g g−1; total lipids = 8.39%; total proteins = 18.7%) was obtained using as nitrogen source a mixture of 25% NaNO3 and 75% (NH4)2SO4, both expressed as nitrogen.

  • influence of ammonium sulphate feeding time on fed batch arthrospira spirulina platensis cultivation and biomass composition with and without ph control
    Bioresource Technology, 2011
    Co-Authors: Mayla Santos Rodrigues, Attilio Converti, Sunao Sato, Livia Seno Ferreira, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract Previous work demonstrated that a mixture of NH4Cl and KNO3 as nitrogen source was beneficial to fed-batch Arthrospira (Spirulina) platensis cultivation, in terms of either lower costs or higher Cell Concentration. On the basis of those results, this study focused on the use of a cheaper nitrogen source mixture, namely (NH4)2SO4 plus NaNO3, varying the ammonium feeding time (T = 7–15 days), either controlling the pH by CO2 addition or not. A. platensis was cultivated in mini-tanks at 30 °C, 156 μmol photons m−2 s−1, and starting Cell Concentration of 400 mg L−1, on a modified Schlosser medium. T = 13 days under pH control were selected as optimum conditions, ensuring the best results in terms of biomass production (Maximum Cell Concentration of 2911 mg L−1, Cell productivity of 179 mg L−1 d−1 and specific growth rate of 0.77 d−1) and satisfactory protein and lipid contents (around 30% each).

  • effects of light intensity and dilution rate on the semicontinuous cultivation of arthrospira spirulina platensis a kinetic monod type approach
    Bioresource Technology, 2011
    Co-Authors: Raquel Pedrosa Bezerra, João Carlos Monteiro De Carvalho, Sunao Sato, Attilio Converti, Patrizia Perego, Erika Yuliana Ortiz Montoya
    Abstract:

    Abstract Semicontinuous cultures were carried out at different dilution rates (D) and light intensities (I) to determine the Maximum productivity of Arthrospira platensis cultivated in helicoidal photobioreactor up to the achievement of pseudo-steady-state conditions. At I = 108 μmol photons m−2 s−1, the semicontinuous regime ensured the highest values of Maximum Cell Concentration (Xm = 5772 ± 113 mg L−1) and productivity (PXS = 1319 ± 25 mg L−1 d−1) at the lowest (D = 0.1 day−1) and the highest (D = 0.3 day−1) dilution rates, respectively. A kinetic model derived from that of Monod was proposed to determine the relationship between the product of light intensity to dilution rate (ID) and the Cell productivity, which were shown to exert a combined influence on this parameter. This result put into evidence that pseudo-steady-state conditions could be modified according to circumstances, conveniently varying one or other of the two independent variables.

  • a new approach to ammonium sulphate feeding for fed batch arthrospira spirulina platensis cultivation in tubular photobioreactor
    Biotechnology Progress, 2010
    Co-Authors: Livia Maria Soares Ferreira, Attilio Converti, Sunao Sato, Mayla Santos Rodrigues, João Carlos Monteiro De Carvalho
    Abstract:

    Arthrospira platensis was cultivated in tubular photobioreactor using different photosynthetic photon flux densities (PPFD) and protocols of (NH₄)₂SO₄ fed-batch supply. Results were evaluated by variance analysis selecting Maximum Cell Concentration (X(m)), Cell productivity (P(x)), nitrogen-to-Cell conversion factor (Y(X/N)) and biomass, protein and lipid contents as responses. At PPFD of 120 and 240 μmol-photons/m² s, a parabolic profile of (NH₄)₂SO₄ addition aiming at producing biomass with 7% nitrogen content ensured X(m) values (14.1 and 12.2 g/L, respectively) comparable to those obtained with NaNO₃. At PPFD of 240 μmol-photons/m² s, P(x) (1.69 g/Ld) was 36% higher, although the photosynthetic efficiency (3.0%) was less than one-half that at PPFD of 120 μmol-photons/m² s. Biomass was shown to be constituted by about 35% proteins and 10% lipids, without any dependence on PPFD or kind of nitrogen source. These results highlight the possible use of (NH₄)₂SO₄ as alternative, cheap nitrogen source for A. platensis cultivation in tubular photobioreactors.

Sunao Sato - One of the best experts on this subject based on the ideXlab platform.

  • ferric sulfate coagulation and powdered activated carbon adsorption as simultaneous treatment to reuse the medium in arthrospira platensis cultivation
    Journal of Chemical Technology & Biotechnology, 2016
    Co-Authors: Ana Lucia Morochojacome, Sunao Sato, J Carvalho
    Abstract:

    BACKGROUND Cyanobacteriae and microalgae industries require large amounts of water for their cultivation. Reusing the Arthrospira platensis culture medium is scarcely evaluated in the literature. This work evaluates coagulation and adsorption as a simultaneous process to treat A. platensis spent medium by applying different Concentrations of powdered activated carbon (PAC) and ferric sulfate (S) and by using different contact times (T) to remove organic matter and pigments. RESULTS The process efficiency was measured by removal of both organic matter and pigments by absorbance at 254 and 440 nm, respectively. The highest Maximum Cell Concentration (4863 ± 64 mg L−1) and protein content values (60.0 ± 0.6%) were observed in a medium treated with optimal conditions using PAC = 40.0 mg L−1, S = 32.8 mg L−1 and T = 36.1 min. Under such conditions, chlorophyll-a biomass content of 24.5 ± 0.6 mg g dry Cell−1 and chlorophyll-a productivity of 16.8 ± 0.1 mg L−1 d−1 were obtained. CONCLUSIONS Coagulation and adsorption as a simultaneus treatment allowing reuse of the spent medium of A. platensis cultivation can diminish not only its production costs but also environmental pollution. The biomass produced in the treated medium contains more protein and chlorophyll than that produced in the standard medium. © 2015 Society of Chemical Industry

  • Evaluation of physicochemical treatment conditions for the reuse of a spent growth medium in Arthrospira platensis cultivation
    Algal Research, 2016
    Co-Authors: Ana Lucia Morocho-jacome, Sunao Sato, Guilherme Favaro Mascioli, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract Arthrospira platensis is a microorganism that is produced worldwide. Its industrial cultivation requires a large quantity of alkaline medium with high salinity that could pollute the environment if discharged with no further treatment. The combined effects of the physicochemical processes of flocculation and adsorption were applied to reuse the spent modified Schlosser medium for seven days of A. platensis fed-batch cultivation using urea as nitrogen source. Different Concentrations of both powdered activated carbon and ferric chloride were evaluated at different contact times to remove organic matter and pigments from the spent medium. The efficiency of the process was measured by evaluating the removal of both organic matter and pigments. The best conditions of treatment that maximized the Cell growth were 24.4 mg L− 1 powdered activated carbon, 20.3 mg L− 1 ferric chloride and 30.4 min of contact time. Under such conditions, organic matter removal was 92.3 ± 0.6%, pigment removal was 95.3 ± 0.6% and the Maximum Cell Concentration was (4.89 ± 0.03) × 103 mg L− 1, approximately 135% higher than in the standard medium [(2.09 ± 0.05) × 103 mg L− 1]. This biomass had 36.1 ± 0.6% protein content, which was also higher than those values obtained in the standard medium (25.8 ± 0.9%).

  • Growth and composition of arthrospira (spirulina) platensis in a tubular photobioreactor using ammonium nitrate as the nitrogen source in a fed-batch process
    Brazilian Journal of Chemical Engineering, 2015
    Co-Authors: L. C. Cruz-martínez, C. K.c. Jesus, Eliane Dalva G Danesi, Marcelo Chuei Matsudo, Sunao Sato, João Carlos M Carvalho
    Abstract:

    NH4NO3 simultaneously provides a readily assimilable nitrogen source (ammonia) and a reserve of nitrogen (nitrate), allowing for an increase in Arthrospira platensis biomass production while reducing the cost of the cultivation medium. In this study, a 22 plus star central composite experimental design combined with response surface methodology was employed to analyze the influence of light intensity (I) and the total amount of added NH4NO3 (Mt) on a bench-scale tubular photobioreactor for fed-batch cultures. The Maximum Cell Concentration (Xm), Cell productivity (PX) and biomass yield on nitrogen (YX/N) were evaluated, as were the protein and lipid contents. Under optimized conditions (I = 148 µmol·photons·m-2·s-1 and Mt = 9.7 mM NH4NO3), Xm = 4710 ±34.4 mg·L-1, PX = 478.9 ±3.8 mg·L-1·d-1 and YX/N = 15.87 ±0.13 mg·mg-1 were obtained. The best conditions for protein content in the biomass (63.2%) were not the same as those that maximized Cell growth (I = 180 µmol·photons·m-2·s-1 and Mt = 22.5 mM NH4NO3). Based on these results, it is possible to conclude that ammonium nitrate is an interesting alternate nitrogen source for the cultivation of A. platensis in a fed-batch process and could be used for other photosynthetic microorganisms.

  • Fed-Batch Cultivation of Arthrospira platensis Using Carbon Dioxide from Alcoholic Fermentation and Urea as Carbon and Nitrogen Sources
    BioEnergy Research, 2013
    Co-Authors: Raquel Pedrosa Bezerra, Marcelo Chuei Matsudo, Sunao Sato, Attilio Converti, João Carlos M Carvalho
    Abstract:

    To reduce CO2 emissions from alcoholic fermentation, Arthrospira platensis was cultivated in tubular photobioreactor using either urea or nitrate as nitrogen sources at different light intensities (60 μmol m−2 s−1 ≤ I ≤ 240 μmol m−2 s−1). The type of carbon source (pure CO2 or CO2 from fermentation) did not show any appreciable influence on the main cultivation parameters, whereas substitution of nitrate for urea increased the nitrogen-to-Cell conversion factor (YX/N), and the Maximum Cell Concentration (Xm) and productivity (PX) increased with I. As a result, the best performance using gaseous emissions from alcoholic fermentation (Xm = 2,960 ± 35 g m−3, PX = 425 ± 5.9 g m−3 day−1 and YX/N = 15 ± 0.2 g g−1) was obtained at I = 120 μmol m−2 s−1 using urea as nitrogen source. The results obtained in this work demonstrate that the combined use of effluents rich in urea and carbon dioxide could be exploited in large-scale cyanobacteria cultivations to reduce not only the production costs of these photosynthetic microorganisms but also the environmental impact associated to the release of greenhouse emissions.

  • arthrospira spirulina platensis cultivation in tubular photobioreactor use of no cost co2 from ethanol fermentation
    Applied Energy, 2012
    Co-Authors: Attilio Converti, Sunao Sato, Livia Seno Ferreira, Mayla Santos Rodrigues, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract The present study aimed at evaluating the production of Arthrospira platensis in tubular photobioreactor using CO2 from ethanol fermentation. The results of these cultivations were compared to those obtained using CO2 from cylinder at different protocols of simultaneous ammonium sulfate and sodium nitrate feeding. Maximum Cell Concentration (Xm), Cell productivity (Px), nitrogen-to-Cell conversion factor (YX/N), and biomass composition (total lipids and proteins) were selected as responses and evaluated by analysis of variance. The source of CO2 did not exert any significant statistical influence on these responses, which means that the flue gas from ethanol fermentation could successfully be used as a carbon source as well as to control the medium pH, thus contributing to reduce the greenhouse effect. The results taken as a whole demonstrated that the best combination of responses mean values (Xm = 4.543 g L−1; Px = 0.460 g L−1 d−1; YX/N = 15.6 g g−1; total lipids = 8.39%; total proteins = 18.7%) was obtained using as nitrogen source a mixture of 25% NaNO3 and 75% (NH4)2SO4, both expressed as nitrogen.

Livia Seno Ferreira - One of the best experts on this subject based on the ideXlab platform.

  • arthrospira spirulina platensis cultivation in tubular photobioreactor use of no cost co2 from ethanol fermentation
    Applied Energy, 2012
    Co-Authors: Attilio Converti, Sunao Sato, Livia Seno Ferreira, Mayla Santos Rodrigues, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract The present study aimed at evaluating the production of Arthrospira platensis in tubular photobioreactor using CO2 from ethanol fermentation. The results of these cultivations were compared to those obtained using CO2 from cylinder at different protocols of simultaneous ammonium sulfate and sodium nitrate feeding. Maximum Cell Concentration (Xm), Cell productivity (Px), nitrogen-to-Cell conversion factor (YX/N), and biomass composition (total lipids and proteins) were selected as responses and evaluated by analysis of variance. The source of CO2 did not exert any significant statistical influence on these responses, which means that the flue gas from ethanol fermentation could successfully be used as a carbon source as well as to control the medium pH, thus contributing to reduce the greenhouse effect. The results taken as a whole demonstrated that the best combination of responses mean values (Xm = 4.543 g L−1; Px = 0.460 g L−1 d−1; YX/N = 15.6 g g−1; total lipids = 8.39%; total proteins = 18.7%) was obtained using as nitrogen source a mixture of 25% NaNO3 and 75% (NH4)2SO4, both expressed as nitrogen.

  • influence of ammonium sulphate feeding time on fed batch arthrospira spirulina platensis cultivation and biomass composition with and without ph control
    Bioresource Technology, 2011
    Co-Authors: Mayla Santos Rodrigues, Attilio Converti, Sunao Sato, Livia Seno Ferreira, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract Previous work demonstrated that a mixture of NH4Cl and KNO3 as nitrogen source was beneficial to fed-batch Arthrospira (Spirulina) platensis cultivation, in terms of either lower costs or higher Cell Concentration. On the basis of those results, this study focused on the use of a cheaper nitrogen source mixture, namely (NH4)2SO4 plus NaNO3, varying the ammonium feeding time (T = 7–15 days), either controlling the pH by CO2 addition or not. A. platensis was cultivated in mini-tanks at 30 °C, 156 μmol photons m−2 s−1, and starting Cell Concentration of 400 mg L−1, on a modified Schlosser medium. T = 13 days under pH control were selected as optimum conditions, ensuring the best results in terms of biomass production (Maximum Cell Concentration of 2911 mg L−1, Cell productivity of 179 mg L−1 d−1 and specific growth rate of 0.77 d−1) and satisfactory protein and lipid contents (around 30% each).

  • fed batch cultivation of arthrospira spirulina platensis potassium nitrate and ammonium chloride as simultaneous nitrogen sources
    Bioresource Technology, 2010
    Co-Authors: Mayla Santos Rodrigues, Attilio Converti, Sunao Sato, Livia Seno Ferreira, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract Arthrospira platensis was cultivated in minitanks at 13 klux, using a mixture of KNO 3 and NH 4 Cl as nitrogen source. Fed-batch daily supply of NH 4 Cl at exponentially-increasing feeding rate allowed preventing ammonia toxicity and nitrogen deficiency, providing high Maximum Cell Concentration ( X m ) and high-quality biomass (21.85 mg chlorophyll g Cells −1 ; 20.5% lipids; 49.8% proteins). A central composite design combined to response surface methodology was utilized to determine the relationships between responses ( X m , Cell productivity and nitrogen-to-Cell conversion factor) and independent variables (KNO 3 and NH 4 Cl Concentrations). Under optimum conditions (15.5 mM KNO 3 ; 14.1 mM NH 4 Cl), X m was 4327 mg L −1 , a value almost coincident with that obtained with only 25.4 mM KNO 3 , but more than twice that obtained with 21.5 mM NH 4 Cl. A 30%-reduction of culture medium cost can be estimated when compared to KNO 3 -batch runs, thus behaving as a cheap alternative for the commercial production of this cyanobacterium.

Mayla Santos Rodrigues - One of the best experts on this subject based on the ideXlab platform.

  • arthrospira spirulina platensis cultivation in tubular photobioreactor use of no cost co2 from ethanol fermentation
    Applied Energy, 2012
    Co-Authors: Attilio Converti, Sunao Sato, Livia Seno Ferreira, Mayla Santos Rodrigues, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract The present study aimed at evaluating the production of Arthrospira platensis in tubular photobioreactor using CO2 from ethanol fermentation. The results of these cultivations were compared to those obtained using CO2 from cylinder at different protocols of simultaneous ammonium sulfate and sodium nitrate feeding. Maximum Cell Concentration (Xm), Cell productivity (Px), nitrogen-to-Cell conversion factor (YX/N), and biomass composition (total lipids and proteins) were selected as responses and evaluated by analysis of variance. The source of CO2 did not exert any significant statistical influence on these responses, which means that the flue gas from ethanol fermentation could successfully be used as a carbon source as well as to control the medium pH, thus contributing to reduce the greenhouse effect. The results taken as a whole demonstrated that the best combination of responses mean values (Xm = 4.543 g L−1; Px = 0.460 g L−1 d−1; YX/N = 15.6 g g−1; total lipids = 8.39%; total proteins = 18.7%) was obtained using as nitrogen source a mixture of 25% NaNO3 and 75% (NH4)2SO4, both expressed as nitrogen.

  • influence of ammonium sulphate feeding time on fed batch arthrospira spirulina platensis cultivation and biomass composition with and without ph control
    Bioresource Technology, 2011
    Co-Authors: Mayla Santos Rodrigues, Attilio Converti, Sunao Sato, Livia Seno Ferreira, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract Previous work demonstrated that a mixture of NH4Cl and KNO3 as nitrogen source was beneficial to fed-batch Arthrospira (Spirulina) platensis cultivation, in terms of either lower costs or higher Cell Concentration. On the basis of those results, this study focused on the use of a cheaper nitrogen source mixture, namely (NH4)2SO4 plus NaNO3, varying the ammonium feeding time (T = 7–15 days), either controlling the pH by CO2 addition or not. A. platensis was cultivated in mini-tanks at 30 °C, 156 μmol photons m−2 s−1, and starting Cell Concentration of 400 mg L−1, on a modified Schlosser medium. T = 13 days under pH control were selected as optimum conditions, ensuring the best results in terms of biomass production (Maximum Cell Concentration of 2911 mg L−1, Cell productivity of 179 mg L−1 d−1 and specific growth rate of 0.77 d−1) and satisfactory protein and lipid contents (around 30% each).

  • a new approach to ammonium sulphate feeding for fed batch arthrospira spirulina platensis cultivation in tubular photobioreactor
    Biotechnology Progress, 2010
    Co-Authors: Livia Maria Soares Ferreira, Attilio Converti, Sunao Sato, Mayla Santos Rodrigues, João Carlos Monteiro De Carvalho
    Abstract:

    Arthrospira platensis was cultivated in tubular photobioreactor using different photosynthetic photon flux densities (PPFD) and protocols of (NH₄)₂SO₄ fed-batch supply. Results were evaluated by variance analysis selecting Maximum Cell Concentration (X(m)), Cell productivity (P(x)), nitrogen-to-Cell conversion factor (Y(X/N)) and biomass, protein and lipid contents as responses. At PPFD of 120 and 240 μmol-photons/m² s, a parabolic profile of (NH₄)₂SO₄ addition aiming at producing biomass with 7% nitrogen content ensured X(m) values (14.1 and 12.2 g/L, respectively) comparable to those obtained with NaNO₃. At PPFD of 240 μmol-photons/m² s, P(x) (1.69 g/Ld) was 36% higher, although the photosynthetic efficiency (3.0%) was less than one-half that at PPFD of 120 μmol-photons/m² s. Biomass was shown to be constituted by about 35% proteins and 10% lipids, without any dependence on PPFD or kind of nitrogen source. These results highlight the possible use of (NH₄)₂SO₄ as alternative, cheap nitrogen source for A. platensis cultivation in tubular photobioreactors.

  • fed batch cultivation of arthrospira spirulina platensis potassium nitrate and ammonium chloride as simultaneous nitrogen sources
    Bioresource Technology, 2010
    Co-Authors: Mayla Santos Rodrigues, Attilio Converti, Sunao Sato, Livia Seno Ferreira, João Carlos Monteiro De Carvalho
    Abstract:

    Abstract Arthrospira platensis was cultivated in minitanks at 13 klux, using a mixture of KNO 3 and NH 4 Cl as nitrogen source. Fed-batch daily supply of NH 4 Cl at exponentially-increasing feeding rate allowed preventing ammonia toxicity and nitrogen deficiency, providing high Maximum Cell Concentration ( X m ) and high-quality biomass (21.85 mg chlorophyll g Cells −1 ; 20.5% lipids; 49.8% proteins). A central composite design combined to response surface methodology was utilized to determine the relationships between responses ( X m , Cell productivity and nitrogen-to-Cell conversion factor) and independent variables (KNO 3 and NH 4 Cl Concentrations). Under optimum conditions (15.5 mM KNO 3 ; 14.1 mM NH 4 Cl), X m was 4327 mg L −1 , a value almost coincident with that obtained with only 25.4 mM KNO 3 , but more than twice that obtained with 21.5 mM NH 4 Cl. A 30%-reduction of culture medium cost can be estimated when compared to KNO 3 -batch runs, thus behaving as a cheap alternative for the commercial production of this cyanobacterium.