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Yu KL, Ong HC, Zaman HB. Integrated energy informatics technology on microalgae-based wastewater treatment to bioenergy production: A review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 368:122085. [PMID: 39142099 DOI: 10.1016/j.jenvman.2024.122085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 06/19/2024] [Accepted: 07/31/2024] [Indexed: 08/16/2024]
Abstract
The production of renewable biofuel through microalgae and green technology can be a promising solution to meet future energy demands whilst reducing greenhouse gases (GHG) emissions and recovering energy for a carbon-neutral bio-economy and environmental sustainability. Recently, the integration of Energy Informatics (EI) technology as an emerging approach has ensured the feasibility and enhancement of microalgal biotechnology and bioenergy applications. Integrating EI technology such as artificial intelligence (AI), predictive modelling systems and life cycle analysis (LCA) in microalgae field applications can improve cost, efficiency, productivity and sustainability. With the approach of EI technology, data-driven insights and decision-making, resource optimization and a better understanding of the environmental impact of microalgae cultivation could be achieved, making it a crucial step in advancing this field and its applications. This review presents the conventional technologies in the microalgae-based system for wastewater treatment and bioenergy production. Furthermore, the recent integration of EI in microalgal technology from the AI application to the modelling and optimization using predictive control systems has been discussed. The LCA and techno-economic assessment (TEA) in the environmental sustainability and economic point of view are also presented. Future challenges and perspectives in the microalgae-based wastewater treatment to bioenergy production integrated with the EI approach, are also discussed in relation to the development of microalgae as the future energy source.
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Affiliation(s)
- Kai Ling Yu
- Department of Engineering, School of Engineering and Technology, Sunway University, No. 5, Jalan Universiti, Bandar Sunway, 47500, Selangor Darul Ehsan, Malaysia; Tan Sri Leo Moggie Distinguished Chair in Energy Informatics, Institute of Informatics and Computing in Energy (IICE), Universiti Tenaga Nasional (UNITEN), Jalan IKRAM-UNITEN, 43000, Kajang, Selangor, Malaysia.
| | - Hwai Chyuan Ong
- Department of Engineering, School of Engineering and Technology, Sunway University, No. 5, Jalan Universiti, Bandar Sunway, 47500, Selangor Darul Ehsan, Malaysia
| | - Halimah Badioze Zaman
- Tan Sri Leo Moggie Distinguished Chair in Energy Informatics, Institute of Informatics and Computing in Energy (IICE), Universiti Tenaga Nasional (UNITEN), Jalan IKRAM-UNITEN, 43000, Kajang, Selangor, Malaysia
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2
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Costa JAV, Zaparoli M, Cassuriaga APA, Cardias BB, Vaz BDS, Morais MGD, Moreira JB. Biochar production from microalgae: a new sustainable approach to wastewater treatment based on a circular economy. Enzyme Microb Technol 2023; 169:110281. [PMID: 37390584 DOI: 10.1016/j.enzmictec.2023.110281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 05/31/2023] [Accepted: 06/23/2023] [Indexed: 07/02/2023]
Abstract
The generation of wastewater due to human activities are the main responsible for environmental problems. These problems are caused by the large amount of organic and inorganic pollutants related to the presence of pesticides, metals, pathogens, drugs and dyes. The photosynthetic treatment of effluents emerges as a sustainable and low-cost alternative for developing wastewater treatment systems based on a circular economy. Chemical compounds present in wastewater can be recovered and reused as a source of nutrients in microalgae cultivation to produce value-added bioproducts. The microalgal biomass produced in the cultivation with effluents has the potential to produce biochar. Biochar is carbon-rich charcoal that can be obtained by converting microalgae biomass through thermal decomposition of organic raw material under limited oxygen supply conditions. Pyrolysis, torrefaction, and hydrothermal carbonization are processes used for biochar synthesis. The application of microalgal biochar as an adsorbent material to remove several compounds present in effluents is an effective and fast treatment. This effectiveness is usually related to the unique physicochemical characteristics of the biochar, such as the presence of functional groups, ion exchange capacity, thermal stability, and high surface area, volume, and pore area. In addition, biochar can be reused in the adsorption process or applied in agriculture for soil correction. In this context, this review article describes the production, characterization, and use of microalgae biochar through a sustainable approach to wastewater treatment, emphasizing its potential in the circular economy. In addition, the article approaches the potential of microalgal biochar as an adsorbent material and its reuse after the adsorption of contaminants, as well as highlights the challenges and future perspectives on this topic.
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Affiliation(s)
- Jorge Alberto Vieira Costa
- Laboratory of Biochemical Engineering, College of Chemistry and Food Engineering, Federal University of Rio Grande, Rio Grande, RS, Brazil; Bioprocess Engineering and Biotechnology Department, Federal University of Paraná, Curitiba, PR, Brazil
| | - Munise Zaparoli
- Bioprocess Engineering and Biotechnology Department, Federal University of Paraná, Curitiba, PR, Brazil
| | - Ana Paula Aguiar Cassuriaga
- Laboratory of Biochemical Engineering, College of Chemistry and Food Engineering, Federal University of Rio Grande, Rio Grande, RS, Brazil
| | - Bruna Barcelos Cardias
- Bioprocess Engineering and Biotechnology Department, Federal University of Paraná, Curitiba, PR, Brazil
| | - Bruna da Silva Vaz
- Laboratory of Microbiology and Biochemistry, College of Chemistry and Food Engineering, Federal Uni-versity of Rio Grande, Rio Grande, RS, Brazil.
| | - Michele Greque de Morais
- Laboratory of Microbiology and Biochemistry, College of Chemistry and Food Engineering, Federal Uni-versity of Rio Grande, Rio Grande, RS, Brazil.
| | - Juliana Botelho Moreira
- Laboratory of Microbiology and Biochemistry, College of Chemistry and Food Engineering, Federal Uni-versity of Rio Grande, Rio Grande, RS, Brazil.
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Benner P, Meier L, Pfeffer A, Krüger K, Oropeza Vargas JE, Weuster-Botz D. Lab-scale photobioreactor systems: principles, applications, and scalability. Bioprocess Biosyst Eng 2022; 45:791-813. [PMID: 35303143 PMCID: PMC9033726 DOI: 10.1007/s00449-022-02711-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 02/14/2022] [Indexed: 12/20/2022]
Abstract
Phototrophic microorganisms that convert carbon dioxide are being explored for their capacity to solve different environmental issues and produce bioactive compounds for human therapeutics and as food additives. Full-scale phototrophic cultivation of microalgae and cyanobacteria can be done in open ponds or closed photobioreactor systems, which have a broad range of volumes. This review focuses on laboratory-scale photobioreactors and their different designs. Illuminated microtiter plates and microfluidic devices offer an option for automated high-throughput studies with microalgae. Illuminated shake flasks are used for simple uncontrolled batch studies. The application of illuminated bubble column reactors strongly emphasizes homogenous gas distribution, while illuminated flat plate bioreactors offer high and uniform light input. Illuminated stirred-tank bioreactors facilitate the application of very well-defined reaction conditions. Closed tubular photobioreactors as well as open photobioreactors like small-scale raceway ponds and thin-layer cascades are applied as scale-down models of the respective large-scale bioreactors. A few other less common designs such as illuminated plastic bags or aquarium tanks are also used mainly because of their relatively low cost, but up-scaling of these designs is challenging with additional light-driven issues. Finally, this review covers recommendations on the criteria for photobioreactor selection and operation while up-scaling of phototrophic bioprocesses with microalgae or cyanobacteria.
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Affiliation(s)
- Philipp Benner
- Department of Energy and Process Engineering, Chair of Biochemical Engineering, Technical University of Munich, TUM School of Engineering and Design, Boltzmannstraße 15, 85748, Garching, Germany
| | - Lisa Meier
- Technical University of Munich, TUM School of Engineering and Design, Boltzmannstraße 15, 85748, Garching, Germany
| | - Annika Pfeffer
- Technical University of Munich, TUM School of Engineering and Design, Boltzmannstraße 15, 85748, Garching, Germany
| | - Konstantin Krüger
- Technical University of Munich, TUM School of Engineering and Design, Boltzmannstraße 15, 85748, Garching, Germany
| | - José Enrique Oropeza Vargas
- Technical University of Munich, TUM School of Engineering and Design, Boltzmannstraße 15, 85748, Garching, Germany
| | - Dirk Weuster-Botz
- Department of Energy and Process Engineering, Chair of Biochemical Engineering, Technical University of Munich, TUM School of Engineering and Design, Boltzmannstraße 15, 85748, Garching, Germany.
- Technical University of Munich, TUM-AlgaeTec Center, 85521, Taufkirchen, Germany.
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Su HY, Wu SW, Chou HH, Lin WH, Chow TJ, Chiu HH, Fei Q, Cheng KK. Recombinant cyanobacteria cultured in CO2 and seawater as feedstock for coproduction of acetoin and succinate by engineered Enterobacter cloacae. J CO2 UTIL 2021. [DOI: 10.1016/j.jcou.2021.101683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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5
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Sen U, Gurol MD. Carbon dioxide delivery and resulting biomass separation in microalgae cultivation using triethanolamine. SEP SCI TECHNOL 2021. [DOI: 10.1080/01496395.2021.1975134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Unal Sen
- Department of Environmental Engineering, Gebze Technical University, Kocaeli, Turkey
| | - Mirat D. Gurol
- Department of Environmental Engineering, Gebze Technical University, Kocaeli, Turkey
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Process Engineering Aspects for the Microbial Conversion of C1 Gases. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2021; 180:33-56. [PMID: 34291298 DOI: 10.1007/10_2021_172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Industrially applied bioprocesses for the reduction of C1 gases (CO2 and/or CO) are based in particular on (syn)gas fermentation with acetogenic bacteria and on photobioprocesses with microalgae. In each case, process engineering characteristics of the autotrophic microorganisms are specified and process engineering aspects for improving gas and electron supply are summarized before suitable bioreactor configurations are discussed for the production of organic products under given economic constraints. Additionally, requirements for the purity of C1 gases are summarized briefly. Finally, similarities and differences in microbial CO2 valorization are depicted comparing gas fermentations with acetogenic bacteria and photobioprocesses with microalgae.
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Portner BW, Endres CH, Brück T, Garbe D. Life cycle greenhouse gas emissions of microalgal fuel from thin-layer cascades. Bioprocess Biosyst Eng 2021; 44:2399-2406. [PMID: 34296327 DOI: 10.1007/s00449-021-02612-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 07/05/2021] [Indexed: 11/24/2022]
Abstract
Thin-layer cascades (TLCs) enable algae cultivation at high cell densities, thus increasing biomass yields and facilitating the harvest process. This makes them a promising technology for industrial-scale algal fuel production. Using Life Cycle Assessment (LCA), we calculate the greenhouse gas (GHG) emissions of aviation fuel produced using algal biomass from TLCs. We find that the impact (81 g CO2e per MJ) is lower than that of fuel from algal biomass cultivated in open race way ponds (94 g CO2e). However, neither of the two cultivation systems achieve sufficient GHG savings for compliance with the Renewable Energy Directive II. Seawater desalination in particular dominates the TLC impact, indicating a trade-off between carbon and water footprint. In both cultivation systems, the mixing power and fertilizer consumption present further significant impacts. There is uncertainty in the correlation between mixing power and algal oil yield, which should be investigated by future experimental studies.
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Affiliation(s)
| | - Christian H Endres
- Bauhaus Luftfahrt e.V., Taufkirchen, Germany
- Werner Siemens-Chair of Synthetic Biotechnology, Garching, Munich, Germany
| | - Thomas Brück
- Werner Siemens-Chair of Synthetic Biotechnology, Garching, Munich, Germany
| | - Daniel Garbe
- Werner Siemens-Chair of Synthetic Biotechnology, Garching, Munich, Germany
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8
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Scognamiglio V, Giardi MT, Zappi D, Touloupakis E, Antonacci A. Photoautotrophs-Bacteria Co-Cultures: Advances, Challenges and Applications. MATERIALS (BASEL, SWITZERLAND) 2021; 14:3027. [PMID: 34199583 PMCID: PMC8199690 DOI: 10.3390/ma14113027] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/29/2021] [Accepted: 05/30/2021] [Indexed: 01/18/2023]
Abstract
Photosynthetic microorganisms are among the fundamental living organisms exploited for millennia in many industrial applications, including the food chain, thanks to their adaptable behavior and intrinsic proprieties. The great multipotency of these photoautotroph microorganisms has been described through their attitude to become biofarm for the production of value-added compounds to develop functional foods and personalized drugs. Furthermore, such biological systems demonstrated their potential for green energy production (e.g., biofuel and green nanomaterials). In particular, the exploitation of photoautotrophs represents a concrete biorefinery system toward sustainability, currently a highly sought-after concept at the industrial level and for the environmental protection. However, technical and economic issues have been highlighted in the literature, and in particular, challenges and limitations have been identified. In this context, a new perspective has been recently considered to offer solutions and advances for the biomanufacturing of photosynthetic materials: the co-culture of photoautotrophs and bacteria. The rational of this review is to describe the recently released information regarding this microbial consortium, analyzing the critical issues, the strengths and the next challenges to be faced for the intentions attainment.
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Affiliation(s)
- Viviana Scognamiglio
- Institute of Crystallography, National Research Council, Via Salaria Km 29.300, Monterotondo, 00015 Rome, Italy; (V.S.); (M.T.G.); (D.Z.)
| | - Maria Teresa Giardi
- Institute of Crystallography, National Research Council, Via Salaria Km 29.300, Monterotondo, 00015 Rome, Italy; (V.S.); (M.T.G.); (D.Z.)
- Biosensor S.r.l., Via Olmetti 44, 00060 Formello, Italy
| | - Daniele Zappi
- Institute of Crystallography, National Research Council, Via Salaria Km 29.300, Monterotondo, 00015 Rome, Italy; (V.S.); (M.T.G.); (D.Z.)
| | - Eleftherios Touloupakis
- Research Institute on Terrestrial Ecosystems, National Research Council, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy;
| | - Amina Antonacci
- Institute of Crystallography, National Research Council, Via Salaria Km 29.300, Monterotondo, 00015 Rome, Italy; (V.S.); (M.T.G.); (D.Z.)
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Laboratory-scale reproduction of lighting conditions for an outdoor vertical column photobioreactor: Theoretical fundamentals and operation of a programmable LED module. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102227] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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10
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Mangi KH, Larbi Z, Legrand J, Pruvost J, Si-Ahmed EK. Passive thermal regulation approach for Algofilm © photobioreactor through phase change. Chem Eng Res Des 2021. [DOI: 10.1016/j.cherd.2021.02.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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Continuous Production of Lipids with Microchloropsis salina in Open Thin-Layer Cascade Photobioreactors on a Pilot Scale. ENERGIES 2021. [DOI: 10.3390/en14020500] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Studies on microalgal lipid production as a sustainable feedstock for biofuels and chemicals are scarce, particularly those on applying open thin-layer cascade (TLC) photobioreactors under dynamic diurnal conditions. Continuous lipid production with Microchloropsis salina was studied in scalable TLC photobioreactors at 50 m2 pilot scale, applying a physically simulated Mediterranean summer climate. A cascade of two serially connected TLC reactors was applied, promoting biomass growth under nutrient-replete conditions in the first reactor, while inducing the accumulation of lipids via nitrogen limitation in the second reactor. Up to 4.1 g L−1 of lipids were continuously produced at productivities of up to 0.27 g L−1 d−1 (1.8 g m2 d−1) at a mean hydraulic residence time of 2.5 d in the first reactor and 20 d in the second reactor. Coupling mass balances with the kinetics of microalgal growth and lipid formation enabled the simulation of phototrophic process performances of M. salina in TLC reactors in batch and continuous operation at the climate conditions studied. This study demonstrates the scalability of continuous microalgal lipid production in TLC reactors with M. salina and provides a TLC reactor model for the realistic simulation of microalgae lipid production processes after re-identification of the model parameters if other microalgae and/or varying climate conditions are applied.
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12
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Lee JW, Lee SH, Han JW, Kim GH. Early Light-Inducible Protein (ELIP) Can Enhance Resistance to Cold-Induced Photooxidative Stress in Chlamydomonas reinhardtii. Front Physiol 2020; 11:1083. [PMID: 32982798 PMCID: PMC7478268 DOI: 10.3389/fphys.2020.01083] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/06/2020] [Indexed: 11/13/2022] Open
Abstract
Cold weather is one of the biggest challenges in establishing a large-scale microalgae culture facility in temperate regions. In order to develop a strain that is resistant to low temperatures and still maintains high photosynthetic efficiency, transgenic studies have been conducted targeting many genes. Early light-inducible proteins (ELIPs) located in thylakoid membranes are known to protect photosynthetic machinery from various environmental stresses in higher plants. An ELIP homolog was identified from Chlamydomonas reinhardtii and named ELIP3. The role of the gene was analyzed in terms of photosynthetic CO2 assimilation under cold stress. Western blot results showed a significant accumulation of ELIP3 when the cells were exposed to cold stress (4°C). High light stress alone did not induce the accumulation of the protein. Enhanced expression of ELIP3 helped survival of the cell under photo-oxidative stress. The influx of CO2 to the photobioreactor induced strong accumulation of ELIP3, and enhanced survival of the cell under high light and cold stress. When the oxidative stress was reduced by adding a ROS quencher, TEMPOL, to the media the expression of ELIP3 was reduced. A knockdown mutant showed much lower photosynthetic efficiency than wild type in low temperature, and died rapidly when it was exposed to high light and cold stress. The overexpression mutant survived significantly longer in the same conditions. Interestingly, knockdown mutants showed negative phototaxis, while the overexpression mutant showed positive phototaxis. These results suggest that ELIP3 may be involved in the regulation of the redox state of the cell and takes important role in protecting the photosystem under photooxidative stress in low temperatures.
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Affiliation(s)
- Ji Woong Lee
- Department of Biological Sciences, Kongju National University, Kongju, South Korea
| | - Seung Hi Lee
- Department of Biological Sciences, Kongju National University, Kongju, South Korea
| | - Jong Won Han
- Department of Applied Bioresource Science, National Marine Biodiversity Institute of Korea, Seocheon, South Korea
| | - Gwang Hoon Kim
- Department of Biological Sciences, Kongju National University, Kongju, South Korea
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High-Density Microalgae Cultivation in Open Thin-Layer Cascade Photobioreactors with Water Recycling. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10113883] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
(1) Background: Recycling of water and non-converted nutrients is considered to be a necessity for an economically viable production of microalgal biomass as a renewable feedstock. However, medium recycling might also have a negative impact on algal growth and productivity due to the accumulation of growth-inhibiting substances. (2) Methods: Consecutive batch processes with repeated water recycling after harvesting of algal biomass were performed with the saline microalga Microchloropsis salina in open thin-layer cascade photobioreactors operated at a physically simulated Mediterranean summer climate. The impact of water recycling on culture performance was studied and the composition of the recycled water was analyzed. (3) Results: Water recycling had no adverse effect on microalgal growth and biomass productivity (14.9−21.3 g m−2 d−1) if all necessary nutrients were regularly replenished and KNO3 was replaced by urea as the nitrogen source to prevent the accumulation of K+ ions. Dissolved organic carbon accumulated in recycled water, probably promoting mixotrophic growth. (4) Conclusion: This study shows that repeated recycling of water is feasible even in high-density cultivation processes with M. salina of more than 30 g L−1 cell dry weight, increasing culture performance while reducing nutrient consumption and circumventing wastewater production.
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Woortman DV, Fuchs T, Striegel L, Fuchs M, Weber N, Brück TB, Rychlik M. Microalgae a Superior Source of Folates: Quantification of Folates in Halophile Microalgae by Stable Isotope Dilution Assay. Front Bioeng Biotechnol 2020; 7:481. [PMID: 32039182 PMCID: PMC6985443 DOI: 10.3389/fbioe.2019.00481] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 12/23/2019] [Indexed: 12/24/2022] Open
Abstract
A multitude of human nutritional supplements based on Chlorella vulgaris biomass has recently been introduced to the specialty food market. In this study, an analysis of total folate contents in Chlorella sp. and a series of marine microalgae was conducted to evaluate folate content in alternative algae-based food production strains. For the first time, total folate content and vitamer distribution in microalgae were analyzed by stable isotope dilution assay (SIDA) using LC-MS/MS, which has demonstrated its superiority with respect to folate quantification. Consistently, high folate contents were detected in all examined microalgae samples. High folate concentrations of 3,460 ± 134 μg/100 g dry biomass were detected in freshly cultivated Chlorella vulgaris, notably also in other well-researched microalgae strains. To that end, the highest folate content currently documented for any algae sample was measured in the marine microalgae Picochlorum sp. isolate with values of 6,470 ± 167 μg/100 g dry biomass. This calls for alternative products based on other algae biomass. Our data indicate that freshwater and marine microalgae provide extremely high concentrations of folates, which warrant further studies on the regulation of pteroylpolyglutamates in algae as well as on bioaccessibility, absorption, and retention in humans.
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Affiliation(s)
- Dirk Volker Woortman
- Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Tobias Fuchs
- Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Lisa Striegel
- Chair of Analytical Food Chemistry, Technical University of Munich, Freising, Germany
| | - Monika Fuchs
- Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Nadine Weber
- Chair of Analytical Food Chemistry, Technical University of Munich, Freising, Germany
| | - Thomas B. Brück
- Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Michael Rychlik
- Chair of Analytical Food Chemistry, Technical University of Munich, Freising, Germany
- Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, QLD, Australia
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Physical and biological fixation of CO 2 with polymeric nanofibers in outdoor cultivations of Chlorella fusca LEB 111. Int J Biol Macromol 2019; 151:1332-1339. [PMID: 31758984 DOI: 10.1016/j.ijbiomac.2019.10.179] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 10/13/2019] [Accepted: 10/22/2019] [Indexed: 11/21/2022]
Abstract
The objective of this study was to cultivate Chlorella fusca LEB 111 with nanofibers indoors and outdoors to verify the effect on CO2 biofixation and macromolecule production. The microalgae were cultured with 10% (w v-1) polyacrylonitrile (PAN)/dimethylformamide (DMF) nanofibers containing 4% (w v-1) iron oxide nanoparticles (NPsFe2O3), which were added to the cultivations at concentrations of 0, 0.1, 0.3 and 0.5 g L-1. The CO2 biofixation was higher in outdoor assays (270.6 and 310.9 mg L-1 d-1) than in indoor assays (124.6 and 131 mg L-1 d-1) with 0.1 and 0.3 g L-1 nanofibers, respectively. The outdoor assays with 0.3 g L-1 nanofibers had 10.9% greater lipid production than the assays without nanofibers. Thus, this first study of outdoor cultivations with nanofibers as physical adsorbents of CO2 showed the effect of nanostructures in maximizing gas biofixation and producing biomolecules that can be used to obtain bioproducts.
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Mitra M, Mishra S. Multiproduct biorefinery from Arthrospira spp. towards zero waste: Current status and future trends. BIORESOURCE TECHNOLOGY 2019; 291:121928. [PMID: 31399315 DOI: 10.1016/j.biortech.2019.121928] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/25/2019] [Accepted: 07/27/2019] [Indexed: 06/10/2023]
Abstract
Considering the high- and low-value product perspectives, Arthrospira spp. are one of the most industrially exploited microalgae. However, currently, the biomass is being utilized for one specific product resulting in a steep upsurge in the overall production cost. Hence, to boost the economic viability of Arthrospira biorefinery process, every high- and low-value products from it ought to be valorized. Envisioning how costlier can be the multiproduct biorefinery concept owing to the downstream processing at an industrial scale, it is quite essential to look for new trends and encouraging solutions. This article intended to propose a sustainable biorefinery in the wake of the current understanding of the present constraints and challenges associated with Arthrospira biorefinery. The current review aimed at defining the future aspects of this biorefinery including integration and optimization of the culture strategy, and, implementation of new ingenious techniques to improve downstream processing (harvesting, extraction, fractionation, and purification).
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Affiliation(s)
- Madhusree Mitra
- Microalgae Group, Division of Biotechnology and Phycology, CSIR-Central Salt and Marine Chemicals Research Institute, India; Academy of Scientific and Innovative Research, CSIR-Central Salt and Marine Chemicals Research Institute, India
| | - Sandhya Mishra
- Microalgae Group, Division of Biotechnology and Phycology, CSIR-Central Salt and Marine Chemicals Research Institute, India; Academy of Scientific and Innovative Research, CSIR-Central Salt and Marine Chemicals Research Institute, India.
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Schädler T, Caballero Cerbon D, de Oliveira L, Garbe D, Brück T, Weuster-Botz D. Production of lipids with Microchloropsis salina in open thin-layer cascade photobioreactors. BIORESOURCE TECHNOLOGY 2019; 289:121682. [PMID: 31271918 DOI: 10.1016/j.biortech.2019.121682] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 06/17/2019] [Accepted: 06/18/2019] [Indexed: 05/22/2023]
Abstract
Microalgal biomass is considered as the most promising feedstock for sustainable production of liquid fuels. Lipid production with Microchloropsis salina was studied in open thin-layer cascade (TLC) photobioreactors with a surface area of 8 m2 applying a physically simulated Mediterranean summer climate. High lipid concentrations of up to 6.6 g L-1 with 46% (w w-1) total lipids in dry cell mass were achieved in two-phase batch processes applying a nitrogen limitation. The two-phase batch process was transferred into a continuously operated reactor cascade of two TLC photobioreactors. Microchloropsis salina cells were produced continuously in the first photobioreactor, whereas continuous lipid production was enabled in the second, nitrogen-limited TLC photobioreactor resulting in continuous production of 3.0 g L-1 lipids with a high overall lipid space-time-yield of 0.2 g L-1 d-1. The control of alkalinity to about 10 mM resulted in high CO2 conversion efficiencies of 84-87%.
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Affiliation(s)
- T Schädler
- Technical University of Munich, Institute of Biochemical Engineering, Boltzmannstr. 15, 85748 Garching, Germany; Technical University of Munich, TUM-AlgaeTec Center, Willy-Messerschmitt-Straße 1, 82024 Taufkirchen, Germany.
| | - D Caballero Cerbon
- Technical University of Munich, Institute of Biochemical Engineering, Boltzmannstr. 15, 85748 Garching, Germany; Technical University of Munich, TUM-AlgaeTec Center, Willy-Messerschmitt-Straße 1, 82024 Taufkirchen, Germany
| | - L de Oliveira
- Technical University of Munich, Institute of Biochemical Engineering, Boltzmannstr. 15, 85748 Garching, Germany; Technical University of Munich, TUM-AlgaeTec Center, Willy-Messerschmitt-Straße 1, 82024 Taufkirchen, Germany
| | - D Garbe
- Technical University of Munich, Werner Siemens-Chair of Synthetic Biotechnology, Lichtenbergstr. 4, 85748 Garching, Germany; Technical University of Munich, TUM-AlgaeTec Center, Willy-Messerschmitt-Straße 1, 82024 Taufkirchen, Germany.
| | - T Brück
- Technical University of Munich, Werner Siemens-Chair of Synthetic Biotechnology, Lichtenbergstr. 4, 85748 Garching, Germany; Technical University of Munich, TUM-AlgaeTec Center, Willy-Messerschmitt-Straße 1, 82024 Taufkirchen, Germany.
| | - D Weuster-Botz
- Technical University of Munich, Institute of Biochemical Engineering, Boltzmannstr. 15, 85748 Garching, Germany; Technical University of Munich, TUM-AlgaeTec Center, Willy-Messerschmitt-Straße 1, 82024 Taufkirchen, Germany.
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Gissibl A, Sun A, Care A, Nevalainen H, Sunna A. Bioproducts From Euglena gracilis: Synthesis and Applications. Front Bioeng Biotechnol 2019; 7:108. [PMID: 31157220 PMCID: PMC6530250 DOI: 10.3389/fbioe.2019.00108] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 04/29/2019] [Indexed: 11/24/2022] Open
Abstract
In recent years, the versatile phototrophic protist Euglena gracilis has emerged as an interesting candidate for application-driven research and commercialisation, as it is an excellent source of dietary protein, pro(vitamins), lipids, and the β-1,3-glucan paramylon only found in euglenoids. From these, paramylon is already marketed as an immunostimulatory agent in nutraceuticals. Bioproducts from E. gracilis can be produced under various cultivation conditions discussed in this review, and their yields are relatively high when compared with those achieved in microalgal systems. Future challenges include achieving the economy of large-scale cultivation. Recent insights into the complex metabolism of E. gracilis have highlighted unique metabolic pathways, which could provide new leads for product enhancement by genetic modification of the organism. Also, development of molecular tools for strain improvement are emerging rapidly, making E. gracilis a noteworthy challenger for microalgae such as Chlorella spp. and their products currently on the market.
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Affiliation(s)
- Alexander Gissibl
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Research Council Industrial Transformation Training Centre for Molecular Technology in the Food Industry, Sydney, NSW, Australia
| | - Angela Sun
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Research Council Industrial Transformation Training Centre for Molecular Technology in the Food Industry, Sydney, NSW, Australia
| | - Andrew Care
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Helena Nevalainen
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Research Council Industrial Transformation Training Centre for Molecular Technology in the Food Industry, Sydney, NSW, Australia
- Biomolecular Discovery and Design Research Centre, Macquarie University, Sydney, NSW, Australia
| | - Anwar Sunna
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Research Council Industrial Transformation Training Centre for Molecular Technology in the Food Industry, Sydney, NSW, Australia
- Biomolecular Discovery and Design Research Centre, Macquarie University, Sydney, NSW, Australia
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Pfaffinger CE, Severin TS, Apel AC, Göbel J, Sauter J, Weuster-Botz D. Light-dependent growth kinetics enable scale-up of well-mixed phototrophic bioprocesses in different types of photobioreactors. J Biotechnol 2019; 297:41-48. [DOI: 10.1016/j.jbiotec.2019.03.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/05/2019] [Accepted: 03/08/2019] [Indexed: 01/02/2023]
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20
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Chen JH, Chen CY, Hasunuma T, Kondo A, Chang CH, Ng IS, Chang JS. Enhancing lutein production with mixotrophic cultivation of Chlorella sorokiniana MB-1-M12 using different bioprocess operation strategies. BIORESOURCE TECHNOLOGY 2019; 278:17-25. [PMID: 30669027 DOI: 10.1016/j.biortech.2019.01.041] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 01/08/2019] [Accepted: 01/09/2019] [Indexed: 06/09/2023]
Abstract
A lutein-enriched mutant, Chlorella sorokiniana MB-1-M12 was grown mixotrophically for lutein production. The lutein production efficiency of the strain was enhanced via optimizing the operating strategies. The results show that using semi-continuous cultivation with a medium replacement ratio of 75% resulted in a higher lutein productivity and lutein concentration of 6.24 mg/L/d and 50.6 mg/L, respectively, which were markedly higher than those obtained from batch and fed-batch cultivation. Cultivation under simulated outdoor cultivation conditions (i.e., temperature of 35 °C/25 °C for a 12 h/12 h light/dark cycle) could achieve the highest lutein productivity and lutein concentration of 3.34 mg/L/d and 30.8 mg/L, respectively. Lutein production via outdoor cultivation of MB-1-M12 strain with a 60-L tubular photobioreactor was performed using semi-continuous operation. With a medium replacement ratio of 75%, a good lutein productivity (4.46 mg/L/d) and concentration (27.4 mg/L) was obtained, indicating the feasibility of producing lutein under outdoor cultivation of the microalgal strain.
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Affiliation(s)
- Jih-Heng Chen
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Chun-Yen Chen
- University Center for Bioscience and Biotechnology, National Cheng Kung University, Tainan 701, Taiwan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada-Ku, Kobe 657-8501, Japan
| | - Akihiko Kondo
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada-Ku, Kobe 657-8501, Japan; Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada-Ku, Kobe 657-8501, Japan
| | - Chien-Hsiang Chang
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - I-Son Ng
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Jo-Shu Chang
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan; Research Center for Energy Technology and Strategy, National Cheng Kung University, Tainan 701, Taiwan; Research Center for Circular Economy, National Cheng Kung University, Tainan 701, Taiwan; College of Engineering, Tunghai University, Taichung 407, Taiwan.
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Severin TS, Brück T, Weuster-Botz D. Validated numerical fluid simulation of a thin-layer cascade photobioreactor in OpenFOAM. Eng Life Sci 2018; 19:97-103. [PMID: 32624991 DOI: 10.1002/elsc.201800097] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 10/24/2018] [Accepted: 11/06/2018] [Indexed: 11/06/2022] Open
Abstract
Recently, microalgae have been considered as a promising alternative for the production of biofuels from CO2. For the efficient cultivation of these microalgae, several types of photobioreactors have been designed and Pilot scale photobioreactors have been used to assess the performance of these reactors. Therein the primarily investigated reactor type is the Raceway Pond. However, the less researched Thin-Layer Cascade Photobioreactor (TLC) shows a high potential for efficient production processes. Unfortunately, for low-value products like biofuels costs must be kept to a minimum for an economic operation. To facilitate this, 3D Computational Fluid Dynamic simulations can be employed to estimate performance of reactor variants e.g. with respect to power input and mixing. Since up to now little effort has been put into the modelling of TLC reactors, this report aims to present a simulation approach for these reactors types that allows simple adaptation to different geometric or operational boundary conditions. All models have been generated for a two-phase mixture in OpenFOAM. To demonstrate its applicability, validation measurements with a physical unit have been performed and were compared to the simulation results. With errors in the order of 10 % a successful simulation of the reactor geometry could be proven.
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Affiliation(s)
- Timm Steffen Severin
- Institute of Biochemical Engineering Technical University of Munich Garching Germany.,TUM AlgaeTec Center Ottobrunn Germany
| | - Thomas Brück
- Werner Siemens-Chair of Synthetic Biotechnology Technical University of Munich Garching Germany.,TUM AlgaeTec Center Ottobrunn Germany
| | - Dirk Weuster-Botz
- Institute of Biochemical Engineering Technical University of Munich Garching Germany.,TUM AlgaeTec Center Ottobrunn Germany
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22
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Niizawa I, Espinaco BY, Leonardi JR, Heinrich JM, Sihufe GA. Enhancement of astaxanthin production from Haematococcus pluvialis under autotrophic growth conditions by a sequential stress strategy. Prep Biochem Biotechnol 2018; 48:528-534. [PMID: 29932803 DOI: 10.1080/10826068.2018.1466159] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The study of microalgal culture has been growing in recent decades, because the cellular structure of microalgae has diverse highly valuable metabolites that have attract attention of numerous companies and research groups. The pigment astaxanthin is considered one of the most powerful antioxidants in nature. The microalga Haematococcus pluvialis was proposed as one of the best natural astaxanthin sources, because it can accumulate high amount of the pigment. In this work, we studied different stress treatments on H. pluvialis growth cultures as well as astaxanthin production under autotrophic growth conditions. The results showed that extending nitrogen starvation before increasing radiation intensity up to 110 μmol photons m-2 s-1 during late the palmella cell phase incremented the astaxanthin concentration up to 2.7% of dry biomass with an efficient light energy utilization during the stress stage.
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Affiliation(s)
- Ignacio Niizawa
- a Instituto de Desarrollo Tecnológico para la Industria Química (INTEC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional del Litoral (UNL) , Santa Fe , Argentina.,b Facultad de Bioquímica y Ciencias Biológicas (FBCB), Universidad Nacional del Litoral (UNL), Ciudad Universitaria (Paraje El Pozo) , Santa Fe , Argentina.,c Grupo de Innovación en Ingeniería de Bioprocesos, Ciudad Universitaria (Paraje El Pozo) , Santa Fe , Argentina
| | - Brenda Yanina Espinaco
- b Facultad de Bioquímica y Ciencias Biológicas (FBCB), Universidad Nacional del Litoral (UNL), Ciudad Universitaria (Paraje El Pozo) , Santa Fe , Argentina.,c Grupo de Innovación en Ingeniería de Bioprocesos, Ciudad Universitaria (Paraje El Pozo) , Santa Fe , Argentina
| | - Jorge Rodrigo Leonardi
- a Instituto de Desarrollo Tecnológico para la Industria Química (INTEC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional del Litoral (UNL) , Santa Fe , Argentina.,b Facultad de Bioquímica y Ciencias Biológicas (FBCB), Universidad Nacional del Litoral (UNL), Ciudad Universitaria (Paraje El Pozo) , Santa Fe , Argentina.,c Grupo de Innovación en Ingeniería de Bioprocesos, Ciudad Universitaria (Paraje El Pozo) , Santa Fe , Argentina
| | - Josué Miguel Heinrich
- a Instituto de Desarrollo Tecnológico para la Industria Química (INTEC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional del Litoral (UNL) , Santa Fe , Argentina.,b Facultad de Bioquímica y Ciencias Biológicas (FBCB), Universidad Nacional del Litoral (UNL), Ciudad Universitaria (Paraje El Pozo) , Santa Fe , Argentina.,c Grupo de Innovación en Ingeniería de Bioprocesos, Ciudad Universitaria (Paraje El Pozo) , Santa Fe , Argentina
| | - Guillermo Adrián Sihufe
- a Instituto de Desarrollo Tecnológico para la Industria Química (INTEC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional del Litoral (UNL) , Santa Fe , Argentina.,b Facultad de Bioquímica y Ciencias Biológicas (FBCB), Universidad Nacional del Litoral (UNL), Ciudad Universitaria (Paraje El Pozo) , Santa Fe , Argentina
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Endres CH, Roth A, Brück TB. Modeling Microalgae Productivity in Industrial-Scale Vertical Flat Panel Photobioreactors. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:5490-5498. [PMID: 29595958 DOI: 10.1021/acs.est.7b05545] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Potentially achievable biomass yields are a decisive performance indicator for the economic viability of mass cultivation of microalgae. In this study, a computer model has been developed and applied to estimate the productivity of microalgae for large-scale outdoor cultivation in vertical flat panel photobioreactors. Algae growth is determined based on simulations of the reactor temperature and light distribution. Site-specific weather and irradiation data are used for annual yield estimations in six climate zones. Shading and reflections between opposing panels and between panels and the ground are dynamically computed based on the reactor geometry and the position of the sun. The results indicate that thin panels (≤0.05 m) are best suited for the assumed cell density of 2 g L-1 and that reactor panels should face in north-south direction. Panel spacings of 0.4-0.75 m at a panel height of 1 m appear most suitable for commercial applications. Under these preconditions, yields of around 10 kg m-2 a-1 are possible for most locations in the U.S. Only in hot climates significantly lower yields have to be expected, as extreme reactor temperatures limit overall productivity.
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Affiliation(s)
- Christian H Endres
- Bauhaus Luftfahrt , Willy-Messerschmitt-Straße 1 , 82024 Taufkirchen , Germany
- Werner Siemens-Chair of Synthetic Biotechnology, Department of Chemistry , Technical University of Munich , Lichtenbergstraße 4 , 85748 Garching , Germany
| | - Arne Roth
- Bauhaus Luftfahrt , Willy-Messerschmitt-Straße 1 , 82024 Taufkirchen , Germany
| | - Thomas B Brück
- Werner Siemens-Chair of Synthetic Biotechnology, Department of Chemistry , Technical University of Munich , Lichtenbergstraße 4 , 85748 Garching , Germany
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24
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Investigation of vertical mixing in thin-layer cascade reactors using computational fluid dynamics. Chem Eng Res Des 2018. [DOI: 10.1016/j.cherd.2018.01.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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25
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Mixotrophic cultivation of microalgae to enhance the quality of lipid for biodiesel application: effects of scale of cultivation and light spectrum on reduction of α-linolenic acid. Bioprocess Biosyst Eng 2017; 41:531-542. [PMID: 29285556 DOI: 10.1007/s00449-017-1888-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 12/21/2017] [Indexed: 10/18/2022]
Abstract
The research on microalgal biodiesel is focused not only on getting the highest lipid productivity but also desired quality of lipid. The experiments were initially conducted on flask scale (1L) using acetate carbon source at different concentrations viz. 0.5, 2, 3 and 4 g L-1. The optimum concentration of acetate was considered for further experiments in two airlift photobioreactors (10 L) equipped separately with red and white LED lights. The Feasibility Index (FI) was derived to analyze the scalability of mixotrophic cultivation based on net carbon fixation in biomass per consumption of total organic carbon. The experimental strategy under mixotrophic mode of cultivation lowered the α-linolenic acid content of lipid by 60-80% as compared to autotrophic cultivation for Scenedesmus abundans species and yielded the highest biomass and lipid productivities, 59 ± 2 and 17 ± 1.8 mg L-1 day-1, respectively. The TOC, nitrate, and phosphate reduction rates were 74.6 ± 3.0, 11.5 ± 1.4, 9.6 ± 2.4 mg L-1 day-1, respectively. The significant change was observed in lipid compositions due to the scale, mode of cultivation, and light spectra. As compared to phototrophic cultivation, biodiesel obtained under mixotrophic cultivation only met standard biodiesel properties. The FI data showed that the mixotrophic cultivation was feasible on moderate concentrations of acetate (2-3 g L-1).
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Furmaniak MA, Misztak AE, Franczuk MD, Wilmotte A, Waleron M, Waleron KF. Edible Cyanobacterial Genus Arthrospira: Actual State of the Art in Cultivation Methods, Genetics, and Application in Medicine. Front Microbiol 2017; 8:2541. [PMID: 29326676 PMCID: PMC5741684 DOI: 10.3389/fmicb.2017.02541] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 12/06/2017] [Indexed: 11/13/2022] Open
Abstract
The cyanobacterial genus Arthrospira appears very conserved and has been divided into five main genetic clusters on the basis of molecular taxonomy markers. Genetic studies of seven Arthrospira strains, including genome sequencing, have enabled a better understanding of those photosynthetic prokaryotes. Even though genetic manipulations have not yet been performed with success, many genomic and proteomic features such as stress adaptation, nitrogen fixation, or biofuel production have been characterized. Many of above-mentioned studies aimed to optimize the cultivation conditions. Factors like the light intensity and quality, the nitrogen source, or different modes of growth (auto-, hetero-, or mixotrophic) have been studied in detail. The scaling-up of the biomass production using photobioreactors, either closed or open, was also investigated to increase the production of useful compounds. The richness of nutrients contained in the genus Arthrospira can be used for promising applications in the biomedical domain. Ingredients such as the calcium spirulan, immulina, C-phycocyanin, and γ-linolenic acid (GLA) show a strong biological activity. Recently, its use in the fight against cancer cells was documented in many publications. The health-promoting action of "Spirulina" has been demonstrated in the case of cardiovascular diseases and age-related conditions. Some compounds also have potent immunomodulatory properties, promoting the growth of beneficial gut microflora, acting as antimicrobial and antiviral. Products derived from Arthrospira were shown to successfully replace biomaterial scaffolds in regenerative medicine. Supplementation with the cyanobacterium also improves the health of livestock and quality of the products of animal origin. They were also used in cosmetic preparations.
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Affiliation(s)
- Magda A Furmaniak
- Chair and Department of Pharmaceutical Microbiology, Medical University of Gdańsk, Gdańsk, Poland
| | - Agnieszka E Misztak
- Department of Biotechnology, Intercollegiate Faculty of Biotechnology of University of Gdańsk and Medical University of Gdańsk, Gdańsk, Poland
| | - Martyna D Franczuk
- Chair and Department of Pharmaceutical Microbiology, Medical University of Gdańsk, Gdańsk, Poland
| | - Annick Wilmotte
- InBios-Centre for Protein Engineering, Department of Life Sciences, University of Liège, Liège, Belgium
| | - Małgorzata Waleron
- Department of Biotechnology, Intercollegiate Faculty of Biotechnology of University of Gdańsk and Medical University of Gdańsk, Gdańsk, Poland
| | - Krzysztof F Waleron
- Chair and Department of Pharmaceutical Microbiology, Medical University of Gdańsk, Gdańsk, Poland
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Strieth D, Ulber R, Muffler K. Application of phototrophic biofilms: from fundamentals to processes. Bioprocess Biosyst Eng 2017; 41:295-312. [PMID: 29198024 DOI: 10.1007/s00449-017-1870-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 11/24/2017] [Indexed: 01/31/2023]
Abstract
Biotechnological production of valuables by microorganisms is commonly achieved by cultivating the cells as suspended solids in an appropriate liquid medium. However, the main portion of these organisms features a surface-attached growth in their native habitats. The utilization of such biofilms shows significant challenges, e.g. concerning control of pH, nutrient supply, and heat/mass transfer. But the use of biofilms might also enable novel and innovative production processes addressing robustness and strength of the applied biocatalyst, for example if variable conditions might occur in the process or a feedstock (substrate) is changed in its composition. Besides the robustness of a biofilm, the high density of the immobilized biocatalyst facilitates a simple separation of the catalyst and the extracellular product, whereas intracellular target compounds occur in a concentrated form; thus, expenses for downstream processing can be drastically reduced. While phototrophic organisms feature a fabulous spectrum of metabolites ranging from biofuels to biologically active compounds, the low cell density of phototrophic suspension cultures is still limiting their application for production processes. The review is focusing on pro- and eukaryotic microalgae featuring the production of valuable compounds and highlights requirements for their cultivation as phototrophic biofilms, i.e. setup as well as operation of biofilm reactors, and modeling of phototrophic growth.
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Affiliation(s)
- D Strieth
- Institute of Bioprocess Engineering, University of Kaiserslautern, Gottlieb-Daimler-Str. 49, 67663, Kaiserslautern, Germany
| | - R Ulber
- Institute of Bioprocess Engineering, University of Kaiserslautern, Gottlieb-Daimler-Str. 49, 67663, Kaiserslautern, Germany
| | - K Muffler
- Department of Life Sciences and Engineering, University of Applied Sciences Bingen, Berlinstr. 109, 55411, Bingen, Germany.
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Ávila-Román J, Talero E, de Los Reyes C, García-Mauriño S, Motilva V. Microalgae-derived oxylipins decrease inflammatory mediators by regulating the subcellular location of NFκB and PPAR-γ. Pharmacol Res 2017; 128:220-230. [PMID: 29129670 DOI: 10.1016/j.phrs.2017.10.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 10/11/2017] [Accepted: 10/17/2017] [Indexed: 12/22/2022]
Abstract
Oxylipins (OXLs) are bioactive molecules generated by the oxidation of fatty acids that promote the resolution of acute inflammation and prevent chronic inflammatory processes through molecular mechanisms that are not well known. We have previously reported the anti-inflammatory activity of microalgae-derived OXLs and OXL-containing biomass in two inflammatory bowel disease (IBD) models: 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced acute colitis and TNBS-induced recurrent colitis. In this study, we examined the in vitro anti-inflammatory mechanism of action of the most abundant OXLs isolated from Chlamydomonas debaryana (13S-HOTE and 13S-HODE) and Nannochloropsis gaditana (15S-HEPE). These OXLs decreased IL-1β and IL-6 pro-inflammatory cytokines production as well as iNOS and COX-2 expression levels in THP-1 macrophages. In addition, OXLs decreased IL-8 production in HT-29 colon cells, the major chemokine produced by these cells. The interaction of OXLs with NFκB and PPAR-γ signaling pathways was studied by confocal microscopy. In THP-1 macrophages and HT-29 colon cells, stimulated by LPS and TNFα respectively, a pre-treatment with 13S-HOTE, 13S-HODE and 15S-HEPE (100μM) resulted in a lower nuclear presence of NFκB in both cell lines. The study of the subcellular localization of PPAR-γ showed that the treatment of THP-1 and HT-29 cells with these OXLs caused the migration of PPAR-γ into the nucleus. Colocalization analysis of both transcription factors in LPS-stimulated THP-1 macrophages showed that the pre-treatment with 13S-HOTE, 13S-HODE or 15S-HEPE lowered nuclear colocalization similar to control value, and increased cytosolic localization above control level. These results indicate that these OXLs could act as agonist of PPAR-γ and consequently inhibit NFκB signaling pathway activation, thus lowering the production of inflammatory markers, highlighting the therapeutic potential of these OXLs in inflammatory diseases such as IBD.
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Affiliation(s)
- Javier Ávila-Román
- Department of Pharmacology, Faculty of Pharmacy, Universidad de Sevilla, Seville, 41012, Spain.
| | - Elena Talero
- Department of Pharmacology, Faculty of Pharmacy, Universidad de Sevilla, Seville, 41012, Spain
| | - Carolina de Los Reyes
- Department of Organic Chemistry, Faculty of Marine and Environmental Sciences, University of Cádiz, Puerto Real, Cádiz, 11510, Spain
| | - Sofía García-Mauriño
- Department of Plant Biology and Ecology, Faculty of Biology, Universidad de Sevilla, Seville, 41012, Spain
| | - Virginia Motilva
- Department of Pharmacology, Faculty of Pharmacy, Universidad de Sevilla, Seville, 41012, Spain
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Koller AP, Wolf L, Brück T, Weuster-Botz D. Studies on the scale-up of biomass production with Scenedesmus spp. in flat-plate gas-lift photobioreactors. Bioprocess Biosyst Eng 2017; 41:213-220. [DOI: 10.1007/s00449-017-1859-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 10/22/2017] [Indexed: 01/07/2023]
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30
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Optimization of Bioethanol In Silico Production Process in a Fed-Batch Bioreactor Using Non-Linear Model Predictive Control and Evolutionary Computation Techniques. ENERGIES 2017. [DOI: 10.3390/en10111763] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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31
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Apel A, Pfaffinger C, Basedahl N, Mittwollen N, Göbel J, Sauter J, Brück T, Weuster-Botz D. Open thin-layer cascade reactors for saline microalgae production evaluated in a physically simulated Mediterranean summer climate. ALGAL RES 2017. [DOI: 10.1016/j.algal.2017.06.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Severin TS, Plamauer S, Apel AC, Brück T, Weuster-Botz D. Rapid salinity measurements for fluid flow characterisation using minimal invasive sensors. Chem Eng Sci 2017. [DOI: 10.1016/j.ces.2017.03.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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33
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Koller AP, Wolf L, Weuster-Botz D. Reaction engineering analysis of Scenedesmus ovalternus in a flat-plate gas-lift photobioreactor. BIORESOURCE TECHNOLOGY 2017; 225:165-174. [PMID: 27889475 DOI: 10.1016/j.biortech.2016.11.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/07/2016] [Accepted: 11/06/2016] [Indexed: 06/06/2023]
Abstract
Microalgal strains of the genus Scenedesmus are a promising resource for commercial biotechnological applications. The temperature-, pH- and light-dependent growth of Scenedesmus ovalternus has been investigated on a laboratory scale. Best batch process performance was obtained at 30°C, pH 8.0 and an incident photon flux density of 1300μmolphotonsm-2s-1 using a flat-plate gas-lift photobioreactor. Highest growth rate (0.11h-1) and space-time yield (1.7±0.1gCDWL-1d-1) were observed when applying these reaction conditions. Biomass concentrations of up to 7.5±0.1gCDWL-1 were achieved within six days (25.0±0.5gCDWm-2d-1). The light-dependent growth kinetics of S. ovalternus was identified using Schuster's light transfer model and Andrews' light inhibition model (KS=545μmolphotonsm-2s-1; KI=2744μmolphotonsm-2s-1; μmax=0.21h-1). The optimal mean integral photon flux density for growth of S. ovalternus was estimated to be 1223μmolphotonsm-2s-1.
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Affiliation(s)
- Anja Pia Koller
- Institute of Biochemical Engineering, Technical University of Munich, Boltzmannstr. 15, 85748 Garching, Germany.
| | - Lara Wolf
- Institute of Biochemical Engineering, Technical University of Munich, Boltzmannstr. 15, 85748 Garching, Germany
| | - Dirk Weuster-Botz
- Institute of Biochemical Engineering, Technical University of Munich, Boltzmannstr. 15, 85748 Garching, Germany.
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Anti-inflammatory effects of an oxylipin-containing lyophilised biomass from a microalga in a murine recurrent colitis model. Br J Nutr 2016; 116:2044-2052. [PMID: 28025954 DOI: 10.1017/s0007114516004189] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Diet and nutritional factors have emerged as possible interventions for inflammatory bowel diseases (IBD), which are characterised by chronic uncontrolled inflammation of the intestinal mucosa. Microalgal species are a promising source of n-3 PUFA and derived oxylipins, which are lipid mediators with a key role in the resolution of inflammation. The aim of the present study was to investigate the effects of an oxylipin-containing lyophilised biomass from Chlamydomonas debaryana on a recurrent 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis mice model. Moderate chronic inflammation of the colon was induced in BALB/c mice by weekly intracolonic instillations of low dose of TNBS. Administration of the lyophilised microalgal biomass started 2 weeks before colitis induction and was continued throughout colitis development. Mice were killed 48 h after the last TNBS challenge. Oral administration of the microalgal biomass reduced TNBS-induced intestinal inflammation, evidenced by an inhibition of body weight loss, an improvement in colon morphology and a decrease in pro-inflammatory cytokines TNF-α, IL-1β, IL-6 and IL-17. This product also down-regulated colonic expressions of inducible nitric oxide, cyclo-oxygenase 2 and NF-κB, as well as increased PPAR-γ. In addition, lyophilised microalgal biomass up-regulated the expressions of the antioxidant transcription factor nuclear factor E2-related factor 2 and the target gene heme oxygenase 1. This study describes for the first time the prophylactic effects of an oxylipin-containing lyophilised microalgae biomass from C. debaryana in the acute phase of a recurrent TNBS-induced colitis model in mice. These findings suggest the potential use of this microalga, or derived oxylipins, as a nutraceutical in the treatment of IBD.
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Pfaffinger CE, Schöne D, Trunz S, Löwe H, Weuster-Botz D. Model-based optimization of microalgae areal productivity in flat-plate gas-lift photobioreactors. ALGAL RES 2016. [DOI: 10.1016/j.algal.2016.10.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Chen Z, Zhang X, Jiang Z, Chen X, He H, Zhang X. Light/dark cycle of microalgae cells in raceway ponds: Effects of paddlewheel rotational speeds and baffles installation. BIORESOURCE TECHNOLOGY 2016; 219:387-391. [PMID: 27504995 DOI: 10.1016/j.biortech.2016.07.108] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 06/06/2023]
Abstract
The aim of this work was to study the light/dark (L/D) cycle in raceway ponds (RWPs) by the computational fluid dynamics (CFD) method via determining the hydrodynamics of culture media and cell trajectories. The effects of paddlewheel rotational speed and flow-deflector baffles installation on the L/D cycle were analyzed. The results indicated that, the L/D cycles of microalgae cells decreased with the increase of the paddlewheel rotational speeds, when the paddlewheel rotational speeds ranged from 5 to 12rpm. In addition, the installation of the flow-deflector baffles in RWPs can greatly increase the light time and the ratio of light time to L/D cycle for microalgae cells. The study provided an effective method to characterize the L/D cycles in RWPs, and may have important implications for designing the effective large-scale microalgae culture system.
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Affiliation(s)
- Zhijie Chen
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; School of Mechanical and Energy Engineering, Jimei University, Xiamen 361021, China
| | - Xinru Zhang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Zeyi Jiang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China.
| | - Xuehui Chen
- School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Hongzhou He
- School of Mechanical and Energy Engineering, Jimei University, Xiamen 361021, China
| | - Xinxin Zhang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
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Koller AP, Löwe H, Schmid V, Mundt S, Weuster-Botz D. Model-supported phototrophic growth studies with Scenedesmus obtusiusculus
in a flat-plate photobioreactor. Biotechnol Bioeng 2016; 114:308-320. [DOI: 10.1002/bit.26072] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 07/13/2016] [Accepted: 08/07/2016] [Indexed: 11/12/2022]
Affiliation(s)
- Anja Pia Koller
- Institute of Biochemical Engineering; Technical University of Munich; Boltzmannstr. 15 85748 Garching Germany
| | - Hannes Löwe
- Systems Biotechnology; Technical University of Munich; Garching Germany
| | - Verena Schmid
- Institute of Biochemical Engineering; Technical University of Munich; Boltzmannstr. 15 85748 Garching Germany
| | - Sabine Mundt
- Department of Pharmaceutical Biology, Institute of Pharmacy; Ernst-Moritz-Arndt-University; Greifswald Germany
| | - Dirk Weuster-Botz
- Institute of Biochemical Engineering; Technical University of Munich; Boltzmannstr. 15 85748 Garching Germany
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Endres CH, Roth A, Brück TB. Thermal Reactor Model for Large-Scale Algae Cultivation in Vertical Flat Panel Photobioreactors. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:3920-3927. [PMID: 26950078 DOI: 10.1021/acs.est.5b05414] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Microalgae can grow significantly faster than terrestrial plants and are a promising feedstock for sustainable value added products encompassing pharmaceuticals, pigments, proteins and most prominently biofuels. As the biomass productivity of microalgae strongly depends on the cultivation temperature, detailed information on the reactor temperature as a function of time and geographical location is essential to evaluate the true potential of microalgae as an industrial feedstock. In the present study, a temperature model for an array of vertical flat plate photobioreactors is presented. It was demonstrated that mutual shading of reactor panels has a decisive effect on the reactor temperature. By optimizing distance and thickness of the panels, the occurrence of extreme temperatures and the amplitude of daily temperature fluctuations in the culture medium can be drastically reduced, while maintaining a high level of irradiation on the panels. The presented model was developed and applied to analyze the suitability of various climate zones for algae production in flat panel photobioreactors. Our results demonstrate that in particular Mediterranean and tropical climates represent favorable locations. Lastly, the thermal energy demand required for the case of active temperature control is determined for several locations.
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Affiliation(s)
- Christian H Endres
- Bauhaus Luftfahrt e. V. , Willy-Messerschmitt-Str. 1, 82024 Taufkirchen, Germany
- Division of Industrial Biocatalysis, Department of Chemistry, Technische Universität München , Lichtenbergstr. 4, 85748 Garching, Germany
| | - Arne Roth
- Bauhaus Luftfahrt e. V. , Willy-Messerschmitt-Str. 1, 82024 Taufkirchen, Germany
| | - Thomas B Brück
- Division of Industrial Biocatalysis, Department of Chemistry, Technische Universität München , Lichtenbergstr. 4, 85748 Garching, Germany
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Application of light-emitting diodes (LEDs) in cultivation of phototrophic microalgae: current state and perspectives. Appl Microbiol Biotechnol 2015; 100:1077-1088. [DOI: 10.1007/s00253-015-7144-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 11/02/2015] [Accepted: 11/04/2015] [Indexed: 10/22/2022]
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Engineering of oleaginous organisms for lipid production. Curr Opin Biotechnol 2015; 36:32-9. [PMID: 26319892 DOI: 10.1016/j.copbio.2015.08.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 07/29/2015] [Accepted: 08/06/2015] [Indexed: 12/18/2022]
Abstract
Phototrophs are attractive candidates for commercial lipid production. Lipid biosynthetic pathways in these organisms have been largely characterized but the mechanisms partitioning resources toward storage lipids are poorly understood. One promising strategy to study and enhance biomass lipid bioproduction in oleaginous microorganisms is to combine genome-scale metabolic modeling and genetic and metabolic engineering. Here we describe recent advances in in vitro, in vivo, and in silico manipulations of phototrophic metabolism that increase total lipid content or redirect lipid production toward more favorable products such as polyunsaturated fatty acids used as nutritional supplements or in biofuel production.
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Kang NK, Jeon S, Kwon S, Koh HG, Shin SE, Lee B, Choi GG, Yang JW, Jeong BR, Chang YK. Effects of overexpression of a bHLH transcription factor on biomass and lipid production in Nannochloropsis salina. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:200. [PMID: 26628914 PMCID: PMC4666162 DOI: 10.1186/s13068-015-0386-9] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 11/16/2015] [Indexed: 05/02/2023]
Abstract
BACKGROUND Microalgae are considered promising alternative energy sources because they consume CO2 and accumulate large amounts of lipids that can be used as biofuel. Nannochloropsis is a particularly promising microalga due to its high growth rate and lipid content, and the availability of genomic information. Transcription factors (TFs) are global regulators of biological pathways by up- or down-regulation of related genes. Among these, basic helix-loop-helix (bHLH) TFs regulate growth, development, and stress responses in plants and animals, and have been identified in microalgae. We identified two bHLH TFs in the genome of N. salina CCMP1776, NsbHLH1, and NsbHLH2, and characterized functions of NsbHLH2 that may be involved in growth and nutrient uptake. RESULTS We obtained NsbHLH2 overexpressing transformants of N. salina CCMP1776 by particle bombardment and confirmed that these were stable transformants. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting using antibodies against the FLAG tag that was attached at the end of the coding sequence confirmed the expression of the NsbHLH2 protein under various culture conditions. The qRT-PCR results also indicated that the endogenous and transgenic expression of NsbHLH2 was reduced under stressed conditions. Overexpression of NsbHLH2 led to increased growth rate in the early growth period, and concomitantly higher nutrient uptake, than wild type (WT). These enhanced growth and nutrient uptake resulted in increased productivities of biomass and FAME. For example, one of the transformants, NsbHLH2 3-6, showed increased biomass productivity by 36 % under the normal condition, and FAME productivity by 33 % under nitrogen limitation condition. Conclusively, the improved growth in the transformants can be associated with the enhanced nutrient uptake. We are currently assessing their potential for scale-up cultivation with positive outcomes. CONCLUSION Overexpression of NsbHLH2 led to enhanced growth rate and nutrient uptake during the early growth phase, and increased biomass and FAME productivity, especially in the later period under normal and stressed conditions. Based on these results, we postulate that NsbHLH2 can be employed for the industrial production of biodiesel from N. salina.
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Affiliation(s)
- Nam Kyu Kang
- />Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Seungjib Jeon
- />Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Sohee Kwon
- />Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Hyun Gi Koh
- />Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Sung-Eun Shin
- />Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Bongsoo Lee
- />Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Gang-Guk Choi
- />Advanced Biomass R&D Center, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Ji-Won Yang
- />Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Byeong-ryool Jeong
- />Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Yong Keun Chang
- />Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
- />Advanced Biomass R&D Center, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
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