The Experts below are selected from a list of 90180 Experts worldwide ranked by ideXlab platform

Akif Undar - One of the best experts on this subject based on the ideXlab platform.

  • Ündar A. Extracorporeal Life Support Systems: alternative vs. conventional circuits. Perfusion
    2016
    Co-Authors: Sameer Khan, Feng Qiu, Rahul Vasavada, Allan Kunselman, Akif Undar
    Abstract:

    Emerging technologies and practices for pediatric and neonatal extracorporeal Life Support (ECLS) are promising. This experiment sought to compare the Medtronic 0800 silicon rubber membrane oxygenator to the Quadrox-iD Pediatric oxygenator in the conventional roller pump circuit, as well as comparing the conventional circuit to an alternative circuit. Three circuits were set up in the experiment. Two conventional roller pump circuits were used to compare the two oxygenators and an alternative circuit consisting of the Quadrox-iD Pediatric oxygenator and Maquet Rotaflow centrifugal pump system was used to identify differences between circuits. All three circuits were primed with Lactated Ringers ’ solution and human blood, with an hematocrit of 40%. Testing occurred at flow rates of 250, 500, and 750 ml/ min at 37°C for mean arterial line pressures of 60, 80, and 100 mmHg. The results of the experiment showed lower pressure drops and greater retention of total hemodynamic energy (THE) across the Quadrox-iD Pediatric oxygenator compared to the Medtronic 0800 oxygenator. Furthermore, the centrifugal pump used in the alternative circuit showed no back flow at flow rates as low as 250 ml/min while, on the other hand, rpm levels were kept below 2200 for flow rates as high as 750 ml/min. Findings Support the usage of the Quadrox-iD Pediatric oxygenator in a circuit utilizing the Maquet Rotaflow centrifugal pump system due to lower pressure drops and greater percentage of THE retained across the circuit. Additional advantages of the alternative circuit include rapid set-up time, easy transport, lower priming volumes, and no gravity-dependent venous drainage system so that it can be situated in close proximity to and at the level of the patient

  • laboratory evaluation of hemolysis and systemic inflammatory response in neonatal nonpulsatile and pulsatile extracorporeal Life Support Systems
    Artificial Organs, 2015
    Co-Authors: Shigang Wang, Allen R Kunselman, Larry D Baer, Conrad Krawiec, Sunil Patel, Jianxun Song, Fengyang Lei, Akif Undar
    Abstract:

    The objective of this study was to compare the systemic inflammatory response and hemolytic characteristics of a conventional roller pump (HL20-NP) and an alternative diagonal pump with nonpulsatile (DP3-NP) and pulsatile mode (DP3-P) in simulated neonatal extracorporeal Life Support (ECLS) Systems. The experimental neonatal ECLS circuits consist of a conventional Jostra HL20 roller pump or an alternative Medos DP3 diagonal pump, and Medos Hilite 800 LT hollow-fiber oxygenator with diffusion membrane. Eighteen sterile circuits were primed with freshly donated whole blood and divided into three groups: conventional HL20 with nonpulsatile flow (HL20-NP), DP3 with nonpulsatile flow (DP3-NP), and DP3 with pulsatile flow (DP3-P). All trials were conducted for durations of 12 h at a flow rate of 500 mL/min at 36°C. Simultaneous blood flow and pressure waveforms were recorded. Blood samples were collected to measure plasma-free hemoglobin (PFH), human tumor necrosis factor-alpha, interleukin-6 (IL-6), and IL-8, in addition to the routine blood gas, lactate dehydrogenase, and lactic acid levels. HL20-NP group had the highest PFH levels (mean ± standard error of the mean) after a 12-h ECLS run, but the difference among groups did not reach statistical significance (HL20-NP group: 907.6 ± 253.1 mg/L, DP3-NP group: 343.7 ± 163.2 mg/L, and DP3-P group: 407.6 ± 156.6 mg/L, P = 0.06). Although there were similar trends but no statistical differences for the levels of proinflammatory cytokines among the three groups, the HL20-NP group had much greater levels than the other groups (P > 0.05). Pulsatile flow generated higher total hemodynamic energy and surplus hemodynamic energy levels at pre-oxygenator and pre-clamp sites (P < 0.01). Our study demonstrated that the alternative diagonal pump ECLS circuits appeared to have less systemic inflammatory response and hemolysis compared with the conventional roller pump ECLS circuit in simulated neonatal ECLS Systems. Pulsatile flow delivered more hemodynamic energy to the pseudo-patient without increased odds of hemolysis compared with the conventional, nonpulsatile roller pump group.

  • evaluation of conventional nonpulsatile and novel pulsatile extracorporeal Life Support Systems in a simulated pediatric extracorporeal Life Support model
    Artificial Organs, 2015
    Co-Authors: Shigang Wang, Akif Undar, Allen R Kunselman, Alissa Evenson, Brian J Chin
    Abstract:

    The objective of this study is to evaluate two extracorporeal Life Support (ECLS) circuits and determine the effect of pulsatile flow on pressure drop, flow/pressure waveforms, and hemodynamic energy levels in a pediatric pseudopatient. One ECLS circuit consisted of a Medos Deltastream DP3 diagonal pump and Hilite 2400 LT oxygenator with arterial/venous tubing. The second circuit consisted of a Maquet RotaFlow centrifugal pump and Quadrox-iD Pediatric oxygenator with arterial/venous tubing. A 14Fr Medtronic Bio-Medicus one-piece pediatric arterial cannula was used for both circuits. All trials were conducted at flow rates ranging from 500 to 2800 mL/min using pulsatile or nonpulsatile flow. The post-cannula pressure was maintained at 50 mm Hg. Blood temperature was maintained at 36°C. Real-time pressure and flow data were recorded using a custom-based data acquisition system. The results showed that the Deltastream DP3 circuit produced surplus hemodynamic energy (SHE) in pulsatile mode at all flow rates, with greater SHE delivery at lower flow rates. Neither circuit produced SHE in nonpulsatile mode. The Deltastream DP3 pump also demonstrated consistently higher total hemodynamic energy at the pre-oxygenator site in pulsatile mode and a lesser pressure drop across the oxygenator. The Deltastream DP3 pump generated physiological pulsatility without backflow and provided increased hemodynamic energy. This novel ECLS circuit demonstrates suitable in vitro performance and adaptability to a wide range of pediatric patients.

  • extracorporeal Life Support Systems alternative vs conventional circuits
    Perfusion, 2011
    Co-Authors: Sameer Khan, Feng Qiu, Rahul Vasavada, Allan Kunselman, Akif Undar
    Abstract:

    Emerging technologies and practices for pediatric and neonatal extracorporeal Life Support (ECLS) are promising. This experiment sought to compare the Medtronic 0800 silicon rubber membrane oxygenator to the Quadrox-iD Pediatric oxygenator in the conventional roller pump circuit, as well as comparing the conventional circuit to an alternative circuit. Three circuits were set up in the experiment. Two conventional roller pump circuits were used to compare the two oxygenators and an alternative circuit consisting of the Quadrox-iD Pediatric oxygenator and Maquet Rotaflow centrifugal pump system was used to identify differences between circuits. All three circuits were primed with Lactated Ringers' solution and human blood, with an hematocrit of 40%. Testing occurred at flow rates of 250, 500, and 750 ml/ min at 37°C for mean arterial line pressures of 60, 80, and 100 mmHg. The results of the experiment showed lower pressure drops and greater retention of total hemodynamic energy (THE) across the Quadrox-iD Pediatric oxygenator compared to the Medtronic 0800 oxygenator. Furthermore, the centrifugal pump used in the alternative circuit showed no back flow at flow rates as low as 250 ml/min while, on the other hand, rpm levels were kept below 2200 for flow rates as high as 750 ml/min. Findings Support the usage of the Quadrox-iD Pediatric oxygenator in a circuit utilizing the Maquet Rotaflow centrifugal pump system due to lower pressure drops and greater percentage of THE retained across the circuit. Additional advantages of the alternative circuit include rapid set-up time, easy transport, lower priming volumes, and no gravity-dependent venous drainage system so that it can be situated in close proximity to and at the level of the patient.

  • comparison of two types of neonatal extracorporeal Life Support Systems with pulsatile and nonpulsatile flow
    Artificial Organs, 2009
    Co-Authors: Nikkole Haines, John L Myers, Shigang Wang, Akif Undar
    Abstract:

    We compared the effects of two neonatal extracorporeal Life Support (ECLS) Systems on circuit pressures and surplus hemodynamic energy levels in a simulated ECLS model. The clinical set-up included the Jostra HL-20 heart–lung machine, either the Medtronic ECMO (0800) or the MEDOS 800LT Systems with company-provided circuit components, a 10 Fr arterial cannula, and a pseudo-patient. We tested the system in nonpulsatile and pulsatile flow modes at two flow rates using a 40/60 glycerin/water blood analog, for a total of 48 trials, with n = 6 for each set-up. The pressure drops over the Medtronic ECLS were significantly higher than those over the MEDOS system regardless of the flow rate or perfusion mode (144.8 ± 0.2 mm Hg vs. 35.7 ± 0.2 mm Hg, respectively, at 500 mL/min in nonpulsatile mode, P < 0.001). The preoxygenator mean arterial pressures were significantly increased and the precannula hemodynamic energy values were decreased with the Medtronic ECLS circuit. These results suggest that the MEDOS ECLS circuit better transmits hemodynamic energy to the patient, keeps mean circuit pressures lower, and has lower pressure drops than the Medtronic Circuit.

Peter Richter - One of the best experts on this subject based on the ideXlab platform.

  • eu cropis euglena gracilis combined regenerative organic food production in space a space experiment testing biological Life Support Systems under lunar and martian gravity
    Microgravity Science and Technology, 2018
    Co-Authors: Jens Hauslage, Adeel Nasir, Sebastian M Strauch, Ina Becker, Julia Krüger, Peter Richter, Olaf Esmann, Ferdinand W M Haag, Julia Stoltze, Gerhild Bornemann
    Abstract:

    Human space exploration needs stable Life Support Systems for the supply of oxygen, water and food for each human explorer due to long term missions. The most promising approach for building stable Life Support Systems is a combination of physico-chemical and biological Systems. These hybrid Systems combine the reliability of physico-chemical and the sustainability of biological Life Support Systems. Also the disadvantages, which are the finite resources of physico-chemical and the imperfect reliability of biological Systems, are mutually balanced. To improve the reliability of biological Life Support Systems, a combination of different biological Systems may stabilize the whole approach during long term operations. The satellite mission Eu:CROPIS (Euglena gracilis: Combined Regenerative Organic-food Production In Space) is a testbed for investigating the behavior of combined biological Life Support Systems under the influence of altered gravity, here, Lunar and Martian gravity. The core Systems are a biological trickle filter for processing urine into a fertilizer solution via nitrification and Euglena gracilis, a photosynthetic protist which is able to produce oxygen and biomass while protecting the whole system against high ammonia concentrations.

  • eu cropis euglena gracilis combined regenerative organic food production in space a space experiment testing biological Life Support Systems under lunar and martian gravity
    Microgravity Science and Technology, 2018
    Co-Authors: Jens Hauslage, Adeel Nasir, Sebastian M Strauch, Ina Becker, Julia Krüger, Peter Richter, Olaf Esmann, Ferdinand W M Haag, Julia Stoltze, Gerhild Bornemann
    Abstract:

    Human space exploration needs stable Life Support Systems for the supply of oxygen, water and food for each human explorer due to long term missions. The most promising approach for building stable Life Support Systems is a combination of physico-chemical and biological Systems. These hybrid Systems combine the reliability of physico-chemical and the sustainability of biological Life Support Systems. Also the disadvantages, which are the finite resources of physico-chemical and the imperfect reliability of biological Systems, are mutually balanced. To improve the reliability of biological Life Support Systems, a combination of different biological Systems may stabilize the whole approach during long term operations. The satellite mission Eu:CROPIS (Euglena gracilis: Combined Regenerative Organic-food Production In Space) is a testbed for investigating the behavior of combined biological Life Support Systems under the influence of altered gravity, here, Lunar and Martian gravity. The core Systems are a biological trickle filter for processing urine into a fertilizer solution via nitrification and Euglena gracilis, a photosynthetic protist which is able to produce oxygen and biomass while protecting the whole system against high ammonia concentrations.

  • amino acids as possible alternative nitrogen source for growth of euglena gracilis z in Life Support Systems
    Life sciences in space research, 2015
    Co-Authors: Peter Richter, Yanjun An, Xugang Li, Adeel Nasir, Sebastian M Strauch, Ina Becker, Martin Schuster, Julia Krüger, Maria Ntefidou, Viktor Daiker
    Abstract:

    Abstract In recent times Euglena gracilis Z was employed as primary producer in closed environmental Life-Support system (CELSS), e.g. in space research. The photosynthetic unicellular flagellate is not capable of utilizing nitrate, nitrite, and urea as nitrogen source. Therefore, ammonium is supplied as an N-source in the lab (provided as diammonium-dihydrogenphosphate, (NH 4 ) 2 HPO 4 ) to E. gracilis cultures. While nitrate exerts low toxicity to organisms, ammonium is harmful for many aquatic organisms especially, at high pH-values, which causes the ionic NH 4 + (low toxicity) to be partially transformed into the highly toxic ammonia, NH 3 . In earlier reports, Euglena gracilis was described to grow with various amino acids as sole N-source. Our aim was to investigate alternatives for (NH 4 ) 2 HPO 4 as N-source with lower toxicity for organisms co-cultivated with Euglena in a CELSS. The growth kinetics of Euglena gracilis cultures was determined in the presence of different amino acids (glycine, glutamine, glutamic acid, leucine, and threonine). In addition, uptake of those amino acids by the cells was measured. Cell growth in the presence of glycine and glutamine was quite comparable to the growth in (NH 4 ) 2 HPO 4 containing cultures while a delay in growth was observed in the presence of leucine and threonine. Unlike, aforementioned amino acids glutamate consumption was very poor. Cell density and glutamate concentration were almost unaltered throughout the experiment and the culture reached the stationary phase within 8 days. The data are compared with earlier studies in which utilization of amino acids in Euglena gracilis was investigated. All tested amino acids (glutamate with limitations) were found to have the potential of being an alternative N-source for Euglena gracilis . Hence, these amino acids can be used as a non-toxic surrogate for (NH 4 ) 2 HPO 4 .

Shigang Wang - One of the best experts on this subject based on the ideXlab platform.

  • laboratory evaluation of hemolysis and systemic inflammatory response in neonatal nonpulsatile and pulsatile extracorporeal Life Support Systems
    Artificial Organs, 2015
    Co-Authors: Shigang Wang, Allen R Kunselman, Larry D Baer, Conrad Krawiec, Sunil Patel, Jianxun Song, Fengyang Lei, Akif Undar
    Abstract:

    The objective of this study was to compare the systemic inflammatory response and hemolytic characteristics of a conventional roller pump (HL20-NP) and an alternative diagonal pump with nonpulsatile (DP3-NP) and pulsatile mode (DP3-P) in simulated neonatal extracorporeal Life Support (ECLS) Systems. The experimental neonatal ECLS circuits consist of a conventional Jostra HL20 roller pump or an alternative Medos DP3 diagonal pump, and Medos Hilite 800 LT hollow-fiber oxygenator with diffusion membrane. Eighteen sterile circuits were primed with freshly donated whole blood and divided into three groups: conventional HL20 with nonpulsatile flow (HL20-NP), DP3 with nonpulsatile flow (DP3-NP), and DP3 with pulsatile flow (DP3-P). All trials were conducted for durations of 12 h at a flow rate of 500 mL/min at 36°C. Simultaneous blood flow and pressure waveforms were recorded. Blood samples were collected to measure plasma-free hemoglobin (PFH), human tumor necrosis factor-alpha, interleukin-6 (IL-6), and IL-8, in addition to the routine blood gas, lactate dehydrogenase, and lactic acid levels. HL20-NP group had the highest PFH levels (mean ± standard error of the mean) after a 12-h ECLS run, but the difference among groups did not reach statistical significance (HL20-NP group: 907.6 ± 253.1 mg/L, DP3-NP group: 343.7 ± 163.2 mg/L, and DP3-P group: 407.6 ± 156.6 mg/L, P = 0.06). Although there were similar trends but no statistical differences for the levels of proinflammatory cytokines among the three groups, the HL20-NP group had much greater levels than the other groups (P > 0.05). Pulsatile flow generated higher total hemodynamic energy and surplus hemodynamic energy levels at pre-oxygenator and pre-clamp sites (P < 0.01). Our study demonstrated that the alternative diagonal pump ECLS circuits appeared to have less systemic inflammatory response and hemolysis compared with the conventional roller pump ECLS circuit in simulated neonatal ECLS Systems. Pulsatile flow delivered more hemodynamic energy to the pseudo-patient without increased odds of hemolysis compared with the conventional, nonpulsatile roller pump group.

  • evaluation of conventional nonpulsatile and novel pulsatile extracorporeal Life Support Systems in a simulated pediatric extracorporeal Life Support model
    Artificial Organs, 2015
    Co-Authors: Shigang Wang, Akif Undar, Allen R Kunselman, Alissa Evenson, Brian J Chin
    Abstract:

    The objective of this study is to evaluate two extracorporeal Life Support (ECLS) circuits and determine the effect of pulsatile flow on pressure drop, flow/pressure waveforms, and hemodynamic energy levels in a pediatric pseudopatient. One ECLS circuit consisted of a Medos Deltastream DP3 diagonal pump and Hilite 2400 LT oxygenator with arterial/venous tubing. The second circuit consisted of a Maquet RotaFlow centrifugal pump and Quadrox-iD Pediatric oxygenator with arterial/venous tubing. A 14Fr Medtronic Bio-Medicus one-piece pediatric arterial cannula was used for both circuits. All trials were conducted at flow rates ranging from 500 to 2800 mL/min using pulsatile or nonpulsatile flow. The post-cannula pressure was maintained at 50 mm Hg. Blood temperature was maintained at 36°C. Real-time pressure and flow data were recorded using a custom-based data acquisition system. The results showed that the Deltastream DP3 circuit produced surplus hemodynamic energy (SHE) in pulsatile mode at all flow rates, with greater SHE delivery at lower flow rates. Neither circuit produced SHE in nonpulsatile mode. The Deltastream DP3 pump also demonstrated consistently higher total hemodynamic energy at the pre-oxygenator site in pulsatile mode and a lesser pressure drop across the oxygenator. The Deltastream DP3 pump generated physiological pulsatility without backflow and provided increased hemodynamic energy. This novel ECLS circuit demonstrates suitable in vitro performance and adaptability to a wide range of pediatric patients.

  • comparison of two types of neonatal extracorporeal Life Support Systems with pulsatile and nonpulsatile flow
    Artificial Organs, 2009
    Co-Authors: Nikkole Haines, John L Myers, Shigang Wang, Akif Undar
    Abstract:

    We compared the effects of two neonatal extracorporeal Life Support (ECLS) Systems on circuit pressures and surplus hemodynamic energy levels in a simulated ECLS model. The clinical set-up included the Jostra HL-20 heart–lung machine, either the Medtronic ECMO (0800) or the MEDOS 800LT Systems with company-provided circuit components, a 10 Fr arterial cannula, and a pseudo-patient. We tested the system in nonpulsatile and pulsatile flow modes at two flow rates using a 40/60 glycerin/water blood analog, for a total of 48 trials, with n = 6 for each set-up. The pressure drops over the Medtronic ECLS were significantly higher than those over the MEDOS system regardless of the flow rate or perfusion mode (144.8 ± 0.2 mm Hg vs. 35.7 ± 0.2 mm Hg, respectively, at 500 mL/min in nonpulsatile mode, P < 0.001). The preoxygenator mean arterial pressures were significantly increased and the precannula hemodynamic energy values were decreased with the Medtronic ECLS circuit. These results suggest that the MEDOS ECLS circuit better transmits hemodynamic energy to the patient, keeps mean circuit pressures lower, and has lower pressure drops than the Medtronic Circuit.

Julia Krüger - One of the best experts on this subject based on the ideXlab platform.

  • eu cropis euglena gracilis combined regenerative organic food production in space a space experiment testing biological Life Support Systems under lunar and martian gravity
    Microgravity Science and Technology, 2018
    Co-Authors: Jens Hauslage, Adeel Nasir, Sebastian M Strauch, Ina Becker, Julia Krüger, Peter Richter, Olaf Esmann, Ferdinand W M Haag, Julia Stoltze, Gerhild Bornemann
    Abstract:

    Human space exploration needs stable Life Support Systems for the supply of oxygen, water and food for each human explorer due to long term missions. The most promising approach for building stable Life Support Systems is a combination of physico-chemical and biological Systems. These hybrid Systems combine the reliability of physico-chemical and the sustainability of biological Life Support Systems. Also the disadvantages, which are the finite resources of physico-chemical and the imperfect reliability of biological Systems, are mutually balanced. To improve the reliability of biological Life Support Systems, a combination of different biological Systems may stabilize the whole approach during long term operations. The satellite mission Eu:CROPIS (Euglena gracilis: Combined Regenerative Organic-food Production In Space) is a testbed for investigating the behavior of combined biological Life Support Systems under the influence of altered gravity, here, Lunar and Martian gravity. The core Systems are a biological trickle filter for processing urine into a fertilizer solution via nitrification and Euglena gracilis, a photosynthetic protist which is able to produce oxygen and biomass while protecting the whole system against high ammonia concentrations.

  • eu cropis euglena gracilis combined regenerative organic food production in space a space experiment testing biological Life Support Systems under lunar and martian gravity
    Microgravity Science and Technology, 2018
    Co-Authors: Jens Hauslage, Adeel Nasir, Sebastian M Strauch, Ina Becker, Julia Krüger, Peter Richter, Olaf Esmann, Ferdinand W M Haag, Julia Stoltze, Gerhild Bornemann
    Abstract:

    Human space exploration needs stable Life Support Systems for the supply of oxygen, water and food for each human explorer due to long term missions. The most promising approach for building stable Life Support Systems is a combination of physico-chemical and biological Systems. These hybrid Systems combine the reliability of physico-chemical and the sustainability of biological Life Support Systems. Also the disadvantages, which are the finite resources of physico-chemical and the imperfect reliability of biological Systems, are mutually balanced. To improve the reliability of biological Life Support Systems, a combination of different biological Systems may stabilize the whole approach during long term operations. The satellite mission Eu:CROPIS (Euglena gracilis: Combined Regenerative Organic-food Production In Space) is a testbed for investigating the behavior of combined biological Life Support Systems under the influence of altered gravity, here, Lunar and Martian gravity. The core Systems are a biological trickle filter for processing urine into a fertilizer solution via nitrification and Euglena gracilis, a photosynthetic protist which is able to produce oxygen and biomass while protecting the whole system against high ammonia concentrations.

  • amino acids as possible alternative nitrogen source for growth of euglena gracilis z in Life Support Systems
    Life sciences in space research, 2015
    Co-Authors: Peter Richter, Yanjun An, Xugang Li, Adeel Nasir, Sebastian M Strauch, Ina Becker, Martin Schuster, Julia Krüger, Maria Ntefidou, Viktor Daiker
    Abstract:

    Abstract In recent times Euglena gracilis Z was employed as primary producer in closed environmental Life-Support system (CELSS), e.g. in space research. The photosynthetic unicellular flagellate is not capable of utilizing nitrate, nitrite, and urea as nitrogen source. Therefore, ammonium is supplied as an N-source in the lab (provided as diammonium-dihydrogenphosphate, (NH 4 ) 2 HPO 4 ) to E. gracilis cultures. While nitrate exerts low toxicity to organisms, ammonium is harmful for many aquatic organisms especially, at high pH-values, which causes the ionic NH 4 + (low toxicity) to be partially transformed into the highly toxic ammonia, NH 3 . In earlier reports, Euglena gracilis was described to grow with various amino acids as sole N-source. Our aim was to investigate alternatives for (NH 4 ) 2 HPO 4 as N-source with lower toxicity for organisms co-cultivated with Euglena in a CELSS. The growth kinetics of Euglena gracilis cultures was determined in the presence of different amino acids (glycine, glutamine, glutamic acid, leucine, and threonine). In addition, uptake of those amino acids by the cells was measured. Cell growth in the presence of glycine and glutamine was quite comparable to the growth in (NH 4 ) 2 HPO 4 containing cultures while a delay in growth was observed in the presence of leucine and threonine. Unlike, aforementioned amino acids glutamate consumption was very poor. Cell density and glutamate concentration were almost unaltered throughout the experiment and the culture reached the stationary phase within 8 days. The data are compared with earlier studies in which utilization of amino acids in Euglena gracilis was investigated. All tested amino acids (glutamate with limitations) were found to have the potential of being an alternative N-source for Euglena gracilis . Hence, these amino acids can be used as a non-toxic surrogate for (NH 4 ) 2 HPO 4 .

Adeel Nasir - One of the best experts on this subject based on the ideXlab platform.

  • eu cropis euglena gracilis combined regenerative organic food production in space a space experiment testing biological Life Support Systems under lunar and martian gravity
    Microgravity Science and Technology, 2018
    Co-Authors: Jens Hauslage, Adeel Nasir, Sebastian M Strauch, Ina Becker, Julia Krüger, Peter Richter, Olaf Esmann, Ferdinand W M Haag, Julia Stoltze, Gerhild Bornemann
    Abstract:

    Human space exploration needs stable Life Support Systems for the supply of oxygen, water and food for each human explorer due to long term missions. The most promising approach for building stable Life Support Systems is a combination of physico-chemical and biological Systems. These hybrid Systems combine the reliability of physico-chemical and the sustainability of biological Life Support Systems. Also the disadvantages, which are the finite resources of physico-chemical and the imperfect reliability of biological Systems, are mutually balanced. To improve the reliability of biological Life Support Systems, a combination of different biological Systems may stabilize the whole approach during long term operations. The satellite mission Eu:CROPIS (Euglena gracilis: Combined Regenerative Organic-food Production In Space) is a testbed for investigating the behavior of combined biological Life Support Systems under the influence of altered gravity, here, Lunar and Martian gravity. The core Systems are a biological trickle filter for processing urine into a fertilizer solution via nitrification and Euglena gracilis, a photosynthetic protist which is able to produce oxygen and biomass while protecting the whole system against high ammonia concentrations.

  • eu cropis euglena gracilis combined regenerative organic food production in space a space experiment testing biological Life Support Systems under lunar and martian gravity
    Microgravity Science and Technology, 2018
    Co-Authors: Jens Hauslage, Adeel Nasir, Sebastian M Strauch, Ina Becker, Julia Krüger, Peter Richter, Olaf Esmann, Ferdinand W M Haag, Julia Stoltze, Gerhild Bornemann
    Abstract:

    Human space exploration needs stable Life Support Systems for the supply of oxygen, water and food for each human explorer due to long term missions. The most promising approach for building stable Life Support Systems is a combination of physico-chemical and biological Systems. These hybrid Systems combine the reliability of physico-chemical and the sustainability of biological Life Support Systems. Also the disadvantages, which are the finite resources of physico-chemical and the imperfect reliability of biological Systems, are mutually balanced. To improve the reliability of biological Life Support Systems, a combination of different biological Systems may stabilize the whole approach during long term operations. The satellite mission Eu:CROPIS (Euglena gracilis: Combined Regenerative Organic-food Production In Space) is a testbed for investigating the behavior of combined biological Life Support Systems under the influence of altered gravity, here, Lunar and Martian gravity. The core Systems are a biological trickle filter for processing urine into a fertilizer solution via nitrification and Euglena gracilis, a photosynthetic protist which is able to produce oxygen and biomass while protecting the whole system against high ammonia concentrations.

  • amino acids as possible alternative nitrogen source for growth of euglena gracilis z in Life Support Systems
    Life sciences in space research, 2015
    Co-Authors: Peter Richter, Yanjun An, Xugang Li, Adeel Nasir, Sebastian M Strauch, Ina Becker, Martin Schuster, Julia Krüger, Maria Ntefidou, Viktor Daiker
    Abstract:

    Abstract In recent times Euglena gracilis Z was employed as primary producer in closed environmental Life-Support system (CELSS), e.g. in space research. The photosynthetic unicellular flagellate is not capable of utilizing nitrate, nitrite, and urea as nitrogen source. Therefore, ammonium is supplied as an N-source in the lab (provided as diammonium-dihydrogenphosphate, (NH 4 ) 2 HPO 4 ) to E. gracilis cultures. While nitrate exerts low toxicity to organisms, ammonium is harmful for many aquatic organisms especially, at high pH-values, which causes the ionic NH 4 + (low toxicity) to be partially transformed into the highly toxic ammonia, NH 3 . In earlier reports, Euglena gracilis was described to grow with various amino acids as sole N-source. Our aim was to investigate alternatives for (NH 4 ) 2 HPO 4 as N-source with lower toxicity for organisms co-cultivated with Euglena in a CELSS. The growth kinetics of Euglena gracilis cultures was determined in the presence of different amino acids (glycine, glutamine, glutamic acid, leucine, and threonine). In addition, uptake of those amino acids by the cells was measured. Cell growth in the presence of glycine and glutamine was quite comparable to the growth in (NH 4 ) 2 HPO 4 containing cultures while a delay in growth was observed in the presence of leucine and threonine. Unlike, aforementioned amino acids glutamate consumption was very poor. Cell density and glutamate concentration were almost unaltered throughout the experiment and the culture reached the stationary phase within 8 days. The data are compared with earlier studies in which utilization of amino acids in Euglena gracilis was investigated. All tested amino acids (glutamate with limitations) were found to have the potential of being an alternative N-source for Euglena gracilis . Hence, these amino acids can be used as a non-toxic surrogate for (NH 4 ) 2 HPO 4 .