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Střížek A, Přibyl P, Lukeš M, Grivalský T, Kopecký J, Galica T, Hrouzek P. Hibberdia magna (Chrysophyceae): a promising freshwater fucoxanthin and polyunsaturated fatty acid producer. Microb Cell Fact 2023; 22:73. [PMID: 37076862 PMCID: PMC10116740 DOI: 10.1186/s12934-023-02061-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 03/14/2023] [Indexed: 04/21/2023] Open
Abstract
BACKGROUND Algae are prominent producers of carotenoids and polyunsaturated fatty acids which are greatly prized in the food and pharmaceutic industry. Fucoxanthin represents a notable high-value carotenoid produced exclusively by algae. Its benefits range far beyond just antioxidant activity and include cancer prevention, anti-diabetes, anti-obesity, and many other positive effects. Accordingly, large-scale microalgae cultivation to produce fucoxanthin and polyunsaturated fatty acids is still under intensive development in the commercial and academic sectors. Industrially exploitable strains are predominantly derived from marine species while comparable freshwater fucoxanthin producers have yet to be explored. RESULTS In this study, we searched for freshwater fucoxanthin producers among photoautotrophic flagellates including members of the class Chrysophyceae. The initial screening turned our attention to the chrysophyte alga Hibberdia magna. We performed a comprehensive cultivation experiments using a temperature × light cross-gradient to assess the impact of these conditions on the target compounds productivity. Here we present the observations that H. magna simultaneously produces fucoxanthin (max. 1.2% dry biomass) and polyunsaturated fatty acids (max. ~ 9.9% dry biomass) and is accessible to routine cultivation in lab-scale conditions. The highest biomass yields were 3.73 g L-1 accompanied by maximal volumetric productivity of 0.54 g L-1 d-1 which are comparable values to marine microalgae fucoxanthin producers in phototrophic mode. H. magna demonstrated different optimal conditions for biomass, fucoxanthin, and fatty acid accumulation. While maximal fucoxanthin productivities were obtained in dim light and moderate temperatures (23 °C× 80 µmol m-2 s-1), the highest PUFA and overall biomass productivities were found in low temperature and high light (17-20 °C × 320-480 µmol m-2 s-1). Thus, a smart biotechnology setup should be designed to fully utilize H. magna biotechnological potential. CONCLUSIONS Our research brings pioneer insight into the biotechnology potential of freshwater autotrophic flagellates and highlights their ability to produce high-value compounds. Freshwater fucoxanthin-producing species are of special importance as the use of sea-water-based media may increase cultivation costs and prohibits inland microalgae production.
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Affiliation(s)
- Antonín Střížek
- Laboratory of Algal Biotechnology, Institute of Microbiology of the Czech Academy of Sciences - Center Algatech, Trebon, Czech Republic
- Centre for Phycology, Institute of Botany of the Czech Academy of Sciences, Trebon, Czech Republic
- Department of Ecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Pavel Přibyl
- Centre for Phycology, Institute of Botany of the Czech Academy of Sciences, Trebon, Czech Republic
| | - Martin Lukeš
- Laboratory of Algal Biotechnology, Institute of Microbiology of the Czech Academy of Sciences - Center Algatech, Trebon, Czech Republic
| | - Tomáš Grivalský
- Laboratory of Algal Biotechnology, Institute of Microbiology of the Czech Academy of Sciences - Center Algatech, Trebon, Czech Republic
| | - Jiří Kopecký
- Laboratory of Algal Biotechnology, Institute of Microbiology of the Czech Academy of Sciences - Center Algatech, Trebon, Czech Republic
| | - Tomáš Galica
- Laboratory of Algal Biotechnology, Institute of Microbiology of the Czech Academy of Sciences - Center Algatech, Trebon, Czech Republic
| | - Pavel Hrouzek
- Laboratory of Algal Biotechnology, Institute of Microbiology of the Czech Academy of Sciences - Center Algatech, Trebon, Czech Republic.
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Barbosa MJ, Janssen M, Südfeld C, D'Adamo S, Wijffels RH. Hypes, hopes, and the way forward for microalgal biotechnology. Trends Biotechnol 2023; 41:452-471. [PMID: 36707271 DOI: 10.1016/j.tibtech.2022.12.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 12/22/2022] [Accepted: 12/27/2022] [Indexed: 01/26/2023]
Abstract
The urge for food security and sustainability has advanced the field of microalgal biotechnology. Microalgae are microorganisms able to grow using (sun)light, fertilizers, sugars, CO2, and seawater. They have high potential as a feedstock for food, feed, energy, and chemicals. Microalgae grow faster and have higher areal productivity than plant crops, without competing for agricultural land and with 100% efficiency uptake of fertilizers. In comparison with bacterial, fungal, and yeast single-cell protein production, based on hydrogen or sugar, microalgae show higher land-use efficiency. New insights are provided regarding the potential of microalgae replacing soy protein, fish oil, and palm oil and being used as cell factories in modern industrial biotechnology to produce designer feed, recombinant proteins, biopharmaceuticals, and vaccines.
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Affiliation(s)
- Maria J Barbosa
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, PO Box 16, Wageningen, 6700, AA, The Netherlands.
| | - Marcel Janssen
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, PO Box 16, Wageningen, 6700, AA, The Netherlands
| | - Christian Südfeld
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, PO Box 16, Wageningen, 6700, AA, The Netherlands
| | - Sarah D'Adamo
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, PO Box 16, Wageningen, 6700, AA, The Netherlands
| | - Rene H Wijffels
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, PO Box 16, Wageningen, 6700, AA, The Netherlands; Biosciences and Aquaculture, Nord University, Bodø, N-8049,Norway
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Helmy M, Elhalis H, Liu Y, Chow Y, Selvarajoo K. Perspective: Multiomics and Machine Learning Help Unleash the Alternative Food Potential of Microalgae. Adv Nutr 2023; 14:1-11. [PMID: 36811582 PMCID: PMC9780023 DOI: 10.1016/j.advnut.2022.11.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 10/31/2022] [Accepted: 11/09/2022] [Indexed: 12/24/2022] Open
Abstract
Food security has become a pressing issue in the modern world. The ever-increasing world population, ongoing COVID-19 pandemic, and political conflicts together with climate change issues make the problem very challenging. Therefore, fundamental changes to the current food system and new sources of alternative food are required. Recently, the exploration of alternative food sources has been supported by numerous governmental and research organizations, as well as by small and large commercial ventures. Microalgae are gaining momentum as an effective source of alternative laboratory-based nutritional proteins as they are easy to grow under variable environmental conditions, with the added advantage of absorbing carbon dioxide. Despite their attractiveness, the utilization of microalgae faces several practical limitations. Here, we discuss both the potential and challenges of microalgae in food sustainability and their possible long-term contribution to the circular economy of converting food waste into feed via modern methods. We also argue that systems biology and artificial intelligence can play a role in overcoming some of the challenges and limitations; through data-guided metabolic flux optimization, and by systematically increasing the growth of the microalgae strains without negative outcomes, such as toxicity. This requires microalgae databases rich in omics data and further developments on its mining and analytics methods.
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Affiliation(s)
- Mohamed Helmy
- Bioinformatics Institute, Agency for Science, Technology and Research (A∗STAR), Singapore; Department of Computer Science, Lakehead University, Ontario, Canada
| | - Hosam Elhalis
- Singapore Institute of Food and Biotechnology Innovation, Agency for Science, Technology and Research (A∗STAR), Singapore, Singapore
| | - Yan Liu
- Institute of Sustainability for Chemistry, Energy and Environment (ISCE(2)), Agency for Science, Technology and Research (A∗STAR), Singapore, Singapore
| | - Yvonne Chow
- Singapore Institute of Food and Biotechnology Innovation, Agency for Science, Technology and Research (A∗STAR), Singapore, Singapore
| | - Kumar Selvarajoo
- Bioinformatics Institute, Agency for Science, Technology and Research (A∗STAR), Singapore; Singapore Institute of Food and Biotechnology Innovation, Agency for Science, Technology and Research (A∗STAR), Singapore, Singapore; Synthetic Biology for Clinical and Technological Innovation, National University of Singapore, Singapore, Singapore; School of Biological Sciences, Nanyang Technological University, Singapore.
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Casanova LM, Mendes LBB, Corrêa TDS, da Silva RB, Joao RR, Macrae A, Vermelho AB. Development of Microalgae Biodiesel: Current Status and Perspectives. Microorganisms 2022; 11:microorganisms11010034. [PMID: 36677325 PMCID: PMC9862501 DOI: 10.3390/microorganisms11010034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 12/07/2022] [Accepted: 12/18/2022] [Indexed: 12/24/2022] Open
Abstract
Microalgae are regarded as a promising source of biodiesel. In contrast with conventional crops currently used to produce commercial biodiesel, microalgae can be cultivated on non-arable land, besides having a higher growth rate and productivity. However, microalgal biodiesel is not yet regarded as economically competitive, compared to fossil fuels and crop-based biodiesel; therefore, it is not commercially produced. This review provides an overall perspective on technologies with the potential to increase efficiency and reduce the general costs of biodiesel production from microalgae. Opportunities and challenges for large-scale production are discussed. We present the current scenario of Brazilian research in the field and show a successful case in the research and development of microalgal biodiesel in open ponds by Petrobras. This publicly held Brazilian corporation has been investing in research in this sector for over a decade.
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Affiliation(s)
- Livia Marques Casanova
- Biotechnology Center-Bioinovar, Institute of Microbiology Paulo de Goes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21941-902, RJ, Brazil
- Correspondence: (L.M.C.); (A.B.V.)
| | | | - Thamiris de Souza Corrêa
- Biotechnology Center-Bioinovar, Institute of Microbiology Paulo de Goes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21941-902, RJ, Brazil
| | | | - Rafael Richard Joao
- Centro de Pesquisa Leopoldo Miguez de Mello, Petrobrás, Rio de Janeiro 21941-915, RJ, Brazil
| | - Andrew Macrae
- Sustainable Biotechnology and Microbial Bioinformatics Laboratory, Institute of Microbiology Paulo de Goes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21941-902, RJ, Brazil
| | - Alane Beatriz Vermelho
- Biotechnology Center-Bioinovar, Institute of Microbiology Paulo de Goes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21941-902, RJ, Brazil
- Correspondence: (L.M.C.); (A.B.V.)
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Zhu C, Ji Y, Du X, Kong F, Chi Z, Zhao Y. A smart and precise mixing strategy for efficient and cost-effective microalgae production in open ponds. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 852:158515. [PMID: 36063957 DOI: 10.1016/j.scitotenv.2022.158515] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 08/17/2022] [Accepted: 08/31/2022] [Indexed: 06/15/2023]
Abstract
Microalgae biotechnology is a great candidate for carbon neutralization, wastewater treatment and the sustainable production of biofuels and food. Efficient and cost-effective microalgae production depends on highly coordinating the resources used for algal growth. However, dynamic natural disturbances such as culture temperature and sunlight can lead to the poor coordination and waste of resources. Open ponds are the most commonly used commercial microalgal production systems, and enhanced mixing can significantly increase their productivity, but mixing energy can be seriously wasted due to dynamic disturbances, presenting a hindrance to further reducing production costs. Herein, a smart and precise mixing strategy was developed for open ponds in which a paddle wheel's stirring speed for an open pond was smartly and precisely controlled in real time based on dynamic variations in light intensity and culture temperature. The proposed technology achieved the same biomass productivity of Spirulina platensis (8.37 g m-2 day-1) as a control with a constant high mixing rate under dynamic disturbances while reducing mixing energy inputs by approximately 30 % compared to the control. This study provides a promising method to address serious resource waste and poor coordination due to dynamic natural disturbances, holding great potential for efficient and cost-effective microalgae production.
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Affiliation(s)
- Chenba Zhu
- Carbon Neutral Innovation Research Center, Xiamen University, Xiamen 361005, China; Institute of Marine Microbes and Ecospheres, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China, 361005.
| | - Yu Ji
- Institute of Biotechnology, RWTH Aachen University, Worringerweg 3, 52074 Aachen, Germany
| | - Xiang Du
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China
| | - Fantao Kong
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China
| | - Zhanyou Chi
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China; Ningbo Institute of Dalian University of Technology, No.26 Yucai Road, Jiangbei District, Ningbo 315016, China
| | - Yunpeng Zhao
- State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China; Ningbo Institute of Dalian University of Technology, No.26 Yucai Road, Jiangbei District, Ningbo 315016, China.
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Tao Y, Liu Z, Zheng J, Zhou J, He D, Ma J. Microalgae production in human urine: Fundamentals, opportunities, and perspectives. Front Microbiol 2022; 13:1067782. [DOI: 10.3389/fmicb.2022.1067782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 11/01/2022] [Indexed: 11/21/2022] Open
Abstract
The biological treatment of source-separated human urine to produce biofuel, nutraceutical, and high-value chemicals is getting increasing attention. Especially, photoautotrophic microalgae can use human urine as media to achieve environmentally and economically viable large-scale cultivation. This review presents a comprehensive overview of the up-to-date advancements in microalgae cultivation employing urine in photobioreactors (PBRs). The standard matrices describing algal growth and nutrient removal/recovery have been summarized to provide a platform for fair comparison among different studies. Specific consideration has been given to the critical operating factors to understand how the PBRs should be maintained to achieve high efficiencies. Finally, we discuss the perspectives that emphasize the impacts of co-existing bacteria, contamination by human metabolites, and genetic engineering on the practical microalgal biomass production in urine.
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Jebali A, Sanchez MR, Hanschen ER, Starkenburg SR, Corcoran AA. Trait drift in microalgae and applications for strain improvement. Biotechnol Adv 2022; 60:108034. [PMID: 36089253 DOI: 10.1016/j.biotechadv.2022.108034] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 08/06/2022] [Accepted: 09/05/2022] [Indexed: 11/29/2022]
Abstract
Microalgae are increasingly used to generate a wide range of commercial products, and there is growing evidence that microalgae-based products can be produced sustainably. However, industrial production of microalgal biomass is not as developed as other biomanufacturing platform technologies. In addition, results of bench-scale research often fail to translate to large-scale or mass production systems. This disconnect may result from trait drift and evolution occurring, through time, in response to unique drivers in each environment, such as cultivation regimes, weather, and pests. Moreover, outdoor and indoor cultivation of microalgae has the potential to impose negative selection pressures, which makes the maintenance of desired traits a challenge. In this context, this review sheds the light on our current understanding of trait drift and evolution in microalgae. We delineate the basics of phenotype plasticity and evolution, with a focus on how microalgae respond under various conditions. In addition, we review techniques that exploit phenotypic plasticity and evolution for strain improvement in view of industrial commercial applications, highlighting associated advantages and shortcomings. Finally, we suggest future research directions and recommendations to overcome unwanted trait drift and evolution in microalgae cultivation.
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Affiliation(s)
- Ahlem Jebali
- New Mexico Consortium, 4200 W. Jemez Road, Los Alamos, NM 87544, USA.
| | - Monica R Sanchez
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA
| | - Erik R Hanschen
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA
| | | | - Alina A Corcoran
- New Mexico Consortium, 4200 W. Jemez Road, Los Alamos, NM 87544, USA
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Kumar L, Mohan L, Anand R, Joshi V, Chugh M, Bharadvaja N. A review on unit operations, challenges, opportunities, and strategies to improve algal based biodiesel and biorefinery. FRONTIERS IN CHEMICAL ENGINEERING 2022. [DOI: 10.3389/fceng.2022.998289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Globally, the demand for energy is increasing with an emphasis on green fuels for a sustainable future. As the urge for alternative fuels is accelerating, microalgae have emerged as a promising source that can not only produce high lipid but many other platform chemicals. Moreover, it is a better alternative in comparison to conventional feedstock due to yearlong easy and mass cultivation, carbon fixation, and value-added products extraction. To date, numerous studies have been done to elucidate these organisms for large-scale fuel production. However, enhancing the lipid synthesis rate and reducing the production cost still remain a major bottleneck for its economic viability. Therefore, this study compiles information on algae-based biodiesel production with an emphasis on its unit operations from strain selection to biofuel production. Additionally, strategies to enhance lipid accumulation by incorporating genetic, and metabolic engineering and the use of leftover biomass for harnessing bio-products have been discussed. Besides, implementing a biorefinery for extracting oil followed by utilizing leftover biomass to generate value-added products such as nanoparticles, biofertilizers, biochar, and biopharmaceuticals has also been discussed.
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Wang S, Mukhambet Y, Esakkimuthu S, Abomohra AELF. Integrated microalgal biorefinery – Routes, energy, economic and environmental perspectives. JOURNAL OF CLEANER PRODUCTION 2022; 348:131245. [DOI: 10.1016/j.jclepro.2022.131245] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Song I, Kim S, Kim J, Oh H, Jang J, Jeong SJ, Baek K, Shin WS, Sim SJ, Jin E. Macular pigment-enriched oil production from genome-edited microalgae. Microb Cell Fact 2022; 21:27. [PMID: 35183173 PMCID: PMC8858528 DOI: 10.1186/s12934-021-01736-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 12/30/2021] [Indexed: 12/03/2022] Open
Abstract
Background The photosynthetic microorganism Chlamydomonas reinhardtii has been approved as generally recognized as safe (GRAS) recently, this can excessively produce carotenoid pigments and fatty acids. Zeaxanthin epoxidase (ZEP), which converts zeaxanthin to violaxanthin, and ADP-glucose pyrophosphorylase (AGP). These are key regulating genes for the xanthophyll and starch pathways in C. reinhardtii respectively. In this study, to produce macular pigment-enriched microalgal oil, we attempted to edit the AGP gene as an additional knock-out target in the zep mutant as a parental strain. Results Using a sequential CRISPR-Cas9 RNP-mediated knock-out method, we generated double knock-out mutants (dZAs), in which both the ZEP and AGP genes were deleted. In dZA1, lutein (2.93 ± 0.22 mg g−1 DCW: dried cell weight), zeaxanthin (3.12 ± 0.30 mg g−1 DCW), and lipids (450.09 ± 25.48 mg g−1 DCW) were highly accumulated in N-deprivation condition. Optimization of the culture medium and process made it possible to produce pigments and oil via one-step cultivation. This optimization process enabled dZAs to achieve 81% higher oil productivity along with similar macular pigment productivity, than the conventional two-step process. The hexane/isopropanol extraction method was developed for the use of macular pigment-enriched microalgal oil for food. As a result, 196 ± 20.1 mg g−1 DCW of edible microalgal oil containing 8.42 ± 0.92 mg g−1 lutein of oil and 7.69 ± 1.03 mg g−1 zeaxanthin of oil was produced. Conclusion Our research showed that lipids and pigments are simultaneously induced in the dZA strain. Since dZAs are generated by introducing pre-assembled sgRNA and Cas9-protein into cells, antibiotic resistance genes or selective markers are not inserted into the genome of dZA, which is advantageous for applying dZA mutant to food. Therefore, the enriched macular pigment oil extracted from improved strains (dZAs) can be further applied to various food products and nutraceuticals. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-021-01736-7.
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Jakhwal P, Kumar Biswas J, Tiwari A, Kwon EE, Bhatnagar A. Genetic and non-genetic tailoring of microalgae for the enhanced production of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) - A review. BIORESOURCE TECHNOLOGY 2022; 344:126250. [PMID: 34728356 DOI: 10.1016/j.biortech.2021.126250] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
The myriad health benefits associated with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) laid the path for their application in the functional foods and nutraceutical industries. Fish being primarily exploited for extraction of EPA and DHA are unsustainable sources; thus, oleaginous microalgae turn out to be an alternative sustainable source. This review paper aims to provide the recent developments in the context of enhancing EPA and DHA production by utilising non-genetic tailoring and genetic tailoring methods. We have also summarized the legislation, public perception, and possible risks associated with the usage of genetically modified microalgae focusing on EPA and DHA production.
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Affiliation(s)
- Parul Jakhwal
- Department of Separation Science, LUT School of Engineering Science, LUT University, Sammonkatu 12, FI-50130, Mikkeli, Finland
| | - Jayanta Kumar Biswas
- Enviromicrobiology, Ecotoxicology and Ecotechnology Research Laboratory, Department of Ecological Studies, University of Kalyani, Kalyani, Nadia 741235, West Bengal, India; International Centre for Ecological Engineering, University of Kalyani, Kalyani 741235, West Bengal, India
| | - Archana Tiwari
- Diatom Research Laboratory, Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh 201301, India
| | - Eilhann E Kwon
- Department of Environment and Energy, Sejong University, Seoul 05006, Republic of Korea
| | - Amit Bhatnagar
- Department of Separation Science, LUT School of Engineering Science, LUT University, Sammonkatu 12, FI-50130, Mikkeli, Finland.
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A Review on Synchronous Microalgal Lipid Enhancement and Wastewater Treatment. ENERGIES 2021. [DOI: 10.3390/en14227687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Microalgae are unicellular photosynthetic eukaryotes that can treat wastewater and provide us with biofuel. Microalgae cultivation utilizing wastewater is a promising approach for synchronous wastewater treatment and biofuel production. However, previous studies suggest that high microalgae biomass production reduces lipid production and vice versa. For cost-effective biofuel production from microalgae, synchronous lipid and biomass enhancement utilizing wastewater is necessary. Therefore, this study brings forth a comprehensive review of synchronous microalgal lipid and biomass enhancement strategies for biofuel production and wastewater treatment. The review emphasizes the appropriate synergy of the microalgae species, culture media, and synchronous lipid and biomass enhancement conditions as a sustainable, efficient solution.
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Genetic engineering of microalgae for enhanced lipid production. Biotechnol Adv 2021; 52:107836. [PMID: 34534633 DOI: 10.1016/j.biotechadv.2021.107836] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 09/09/2021] [Accepted: 09/09/2021] [Indexed: 12/24/2022]
Abstract
Microalgae have the potential to become microbial cell factories for lipid production. Their ability to convert sunlight and CO2 into valuable lipid compounds has attracted interest from cosmetic, biofuel, food and feed industries. In order to make microalgae-derived products cost-effective and commercially competitive, enhanced growth rates and lipid productivities are needed, which require optimization of cultivation systems and strain improvement. Advances in genetic tool development and omics technologies have increased our understanding of lipid metabolism, which has opened up possibilities for targeted metabolic engineering. In this review we provide a comprehensive overview on the developments made to genetically engineer microalgal strains over the last 30 years. We focus on the strategies that lead to an increased lipid content and altered fatty acid profile. These include the genetic engineering of the fatty acid synthesis pathway, Kennedy pathway, polyunsaturated fatty acid and triacylglycerol metabolisms and fatty acid catabolism. Moreover, genetic engineering of specific transcription factors, NADPH generation and central carbon metabolism, which lead to increase of lipid accumulation are also reviewed.
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A critical perspective on the scope of interdisciplinary approaches used in fourth-generation biofuel production. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102436] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Tanvir RU, Zhang J, Canter T, Chen D, Lu J, Hu Z. Harnessing Solar Energy using Phototrophic Microorganisms: A Sustainable Pathway to Bioenergy, Biomaterials, and Environmental Solutions. RENEWABLE & SUSTAINABLE ENERGY REVIEWS 2021; 146:1-111181. [PMID: 34526853 PMCID: PMC8437043 DOI: 10.1016/j.rser.2021.111181] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Phototrophic microorganisms (microbial phototrophs) use light as an energy source to carry out various metabolic processes producing biomaterials and bioenergy and supporting their own growth. Among them, microalgae and cyanobacteria have been utilized extensively for bioenergy, biomaterials, and environmental applications. Their superior photosynthetic efficiency, lipid content, and shorter cultivation time compared to terrestrial biomass make them more suitable for efficient production of bioenergy and biomaterials. Other phototrophic microorganisms, especially anoxygenic phototrophs, demonstrated the ability to survive and flourish while producing renewable energy and high-value products under harsh environmental conditions. This review presents a comprehensive overview of microbial phototrophs on their (i) production of bioenergy and biomaterials, (ii) emerging and innovative applications for environmental conservation, mitigation, and remediation, and (iii) physical, genetic, and metabolic pathways to improve light harvesting and biomass/biofuel/biomaterial production. Both physical (e.g., incremental irradiation) and genetic approaches (e.g., truncated antenna) are implemented to increase the light-harvesting efficiency. Increases in biomass yield and metabolic products are possible through the manipulation of metabolic pathways and selection of a proper strain under optimal cultivation conditions and downstream processing, including harvesting, extraction, and purification. Finally, the current barriers in harnessing solar energy using phototrophic microorganisms are presented, and future research perspectives are discussed, such as integrating phototrophic microorganisms with emerging technologies.
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Affiliation(s)
- Rahamat Ullah Tanvir
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, Missouri, 65211, USA
| | - Jianying Zhang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Timothy Canter
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, Missouri, 65211, USA
| | - Dick Chen
- Dual Enrollment Program, University of Missouri, Columbia, Missouri, 65211, USA
| | - Jingrang Lu
- Office of Research and Development, United States Environmental Protection Agency (EPA), Cincinnati, Ohio, 45268, USA
| | - Zhiqiang Hu
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, Missouri, 65211, USA
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Liu X, Zhang D, Zhang J, Chen Y, Liu X, Fan C, Wang RRC, Hou Y, Hu Z. Overexpression of the Transcription Factor AtLEC1 Significantly Improved the Lipid Content of Chlorella ellipsoidea. Front Bioeng Biotechnol 2021; 9:626162. [PMID: 33681161 PMCID: PMC7925920 DOI: 10.3389/fbioe.2021.626162] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 02/02/2021] [Indexed: 12/28/2022] Open
Abstract
Microalgae are considered to be a highly promising source for the production of biodiesel. However, the regulatory mechanism governing lipid biosynthesis has not been fully elucidated to date, and the improvement of lipid accumulation in microalgae is essential for the effective production of biodiesel. In this study, LEAFY COTYLEDON1 (LEC1) from Arabidopsis thaliana, a transcription factor (TF) that affects lipid content, was transferred into Chlorella ellipsoidea. Compared with wild-type (WT) strains, the total fatty acid content and total lipid content of AtLEC1 transgenic strains were significantly increased by 24.20–32.65 and 22.14–29.91%, respectively, under mixotrophic culture conditions and increased by 24.4–28.87 and 21.69–30.45%, respectively, under autotrophic conditions, while the protein content of the transgenic strains was significantly decreased by 18.23–21.44 and 12.28–18.66%, respectively, under mixotrophic and autotrophic conditions. Fortunately, the lipid and protein content variation did not affect the growth rate and biomass of transgenic strains under the two culture conditions. According to the transcriptomic data, the expression of 924 genes was significantly changed in the transgenic strain (LEC1-1). Of the 924 genes, 360 were upregulated, and 564 were downregulated. Based on qRT-PCR results, the expression profiles of key genes in the lipid synthesis pathway, such as ACCase, GPDH, PDAT1, and DGAT1, were significantly changed. By comparing the differentially expressed genes (DEGs) regulated by AtLEC1 in C. ellipsoidea and Arabidopsis, we observed that approximately 59% (95/160) of the genes related to lipid metabolism were upregulated in AtLEC1 transgenic Chlorella. Our research provides a means of increasing lipid content by introducing exogenous TF and presents a possible mechanism of AtLEC1 regulation of lipid accumulation in C. ellipsoidea.
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Affiliation(s)
- Xiao Liu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Dan Zhang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China.,Analysis and Test Center, Guangzhou Higher Education Mega Center, Guangdong University of Technology, Guangzhou, China
| | - Jianhui Zhang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Yuhong Chen
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Xiuli Liu
- Inner Mongolia Academy of Agriculture and Animal Husbandry, Huhhot, China
| | - Chengming Fan
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Richard R-C Wang
- United States Department of Agriculture, Agricultural Research Service, Forage and Range Research Laboratory, Utah State University, Logan, UT, United States
| | - Yongyue Hou
- Inner Mongolia Academy of Agriculture and Animal Husbandry, Huhhot, China
| | - Zanmin Hu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China.,College of Agriculture, University of Chinese Academy of Sciences, Beijing, China
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17
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Chakdar H, Hasan M, Pabbi S, Nevalainen H, Shukla P. High-throughput proteomics and metabolomic studies guide re-engineering of metabolic pathways in eukaryotic microalgae: A review. BIORESOURCE TECHNOLOGY 2021; 321:124495. [PMID: 33307484 DOI: 10.1016/j.biortech.2020.124495] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/24/2020] [Accepted: 11/28/2020] [Indexed: 06/12/2023]
Abstract
Eukaryotic microalgae are a rich source of commercially important metabolites including lipids, pigments, sugars, amino acids and enzymes. However, their inherent genetic potential is usually not enough to support high level production of metabolites of interest. In order to move on from the traditional approach of improving product yields by modification of the cultivation conditions, understanding the metabolic pathways leading to the synthesis of the bioproducts of interest is crucial. Identification of new targets for strain engineering has been greatly facilitated by the rapid development of high-throughput sequencing and spectroscopic techniques discussed in this review. Despite the availability of high throughput analytical tools, examples of gathering and application of proteomic and metabolomic data for metabolic engineering of microalgae are few and mainly limited to lipid production. The present review highlights the application of contemporary proteomic and metabolomic techniques in eukaryotic microalgae for redesigning pathways for enhanced production of algal metabolites.
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Affiliation(s)
- Hillol Chakdar
- ICAR-National Bureau of Agriculturally Important Microorganisms (NBAIM), Maunath Bhanjan, Uttar Pradesh 275103, India
| | - Mafruha Hasan
- School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia
| | - Sunil Pabbi
- Centre for Conservation and Utilisation of Blue Green Algae (CCUBGA), Division of Microbiology, ICAR - Indian Agricultural Research Institute, New Delhi 110 012
| | - Helena Nevalainen
- Department of Molecular Sciences, Macquarie University, NSW 2109, Australia; Biomolecular Discovery and Design Research Centre, Macquarie University, Sydney, NSW 2109, Australia
| | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak 124001, Haryana, India; School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi 221005, India.
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18
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Abstract
We have had high expectations for using algae biodiesel for many years, but the quantities of biodiesel currently produced from algae are tiny compared to the quantities of conventional diesel oil. Furthermore, no comprehensive analysis of the impact of all factors on the market production of algal biodiesel has been made so far. This paper aims to analyze the strengths, weaknesses, opportunities, and threats associated with algal biodiesel, to evaluate its production prospects for the biofuels market. The results of the analysis show that it is possible to increase the efficiency of algae biomass production further. However, because the production of this biodiesel is an energy-intensive process, the price of biodiesel is high. Opportunities for more economical production of algal biodiesel are seen in integration with other processes, such as wastewater treatment, but this does not ensure large-scale production. The impact of state policies and laws is significant in the future of algal biodiesel production. With increasingly stringent environmental requirements, electric cars are a significant threat to biodiesel production. By considering all the influencing factors, it is not expected that algal biodiesel will gain an essential place in the fuel market.
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19
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CRISPR/Cas technology promotes the various application of Dunaliella salina system. Appl Microbiol Biotechnol 2020; 104:8621-8630. [PMID: 32918585 DOI: 10.1007/s00253-020-10892-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 09/01/2020] [Accepted: 09/05/2020] [Indexed: 12/15/2022]
Abstract
Dunaliella salina (D. salina) has been widely applied in various fields because of its inherent advantages, such as the study of halotolerant mechanism, wastewater treatment, recombinant proteins expression, biofuel production, preparation of natural materials, and others. However, owing to the existence of low yield or in the laboratory exploration stage, D. salina system has been greatly restricted for practical production of various components. In past decade, significant progresses have been achieved for research of D. salina in these fields. Among them, D. salina as a novel expression system demonstrated a bright prospect, especially for large-scale production of foreign proteins, like the vaccines, antibodies, and other therapeutic proteins. Due to the low efficiency, application of traditional regulation tools is also greatly limited for exploration of D. salina system. The emergence of the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas system offers a precise editing tool to overcome the obstacles of D. salina system. This review not only comprehensively summarizes the recent progresses of D. salina in domain of gene engineering but also gives a deep analysis of problems and deficiencies in different fields of D. salina. Moreover, further prospects of CRISPR/Cas system and its significant challenges have been discussed in various aspects of D. salina. It provides a great referencing value for speeding up the maturity of D. salina system, and also supplies practical guiding significance to expand the new application fields for D. salina. KEY POINTS: • The review provides recent research progresses of various applications of D. salina. • The problems and deficiencies in different fields of D. salina were deeply analyzed. • The further prospects of CRISPR/Cas technology in D. salina system were predicted. • CRISPR/Cas system will promote the new application fields and maturity for D. salina.
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20
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Arif M, Bai Y, Usman M, Jalalah M, Harraz FA, Al-Assiri MS, Li X, Salama ES, Zhang C. Highest accumulated microalgal lipids (polar and non-polar) for biodiesel production with advanced wastewater treatment: Role of lipidomics. BIORESOURCE TECHNOLOGY 2020; 298:122299. [PMID: 31706891 DOI: 10.1016/j.biortech.2019.122299] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 10/16/2019] [Accepted: 10/17/2019] [Indexed: 06/10/2023]
Abstract
Microalgal lipids consist of non-polar and polar lipids. Triacyleglyceride (TAG), a non-polar lipid, is convertible to biodiesel, whereas glycolipids and phospholipids are polar and not convertible to biodiesel owing to their high degree of unsaturation (polyunsaturated fatty acids), which makes the production process insufficient and expensive. In this review, microalgal species that contain the highest lipid content (≥40%) in the literature till 2019 are highlighted. The differentiation between non-polar and polar lipids and the limitations in the conversion of polar lipids to biodiesel are reported. The basic and advanced factors contributing to the accumulation of lipids convertible to biodiesel is discussed. Microalgal species including Scenedesmus obliquus, Ourococcus multisporus, Chlamydomonas pitschmannii, Micractinium reisseri, and Botryococcus braunii with high lipid content are potential candidates for biomass/biodiesel production and nutrient removal from wastewater. Application of lipidomics and transcriptomics to manipulate the lipid associated gene acetyl-CoA synthetase in microalgae improves the accumulative lipid content.
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Affiliation(s)
- Muhammad Arif
- School of Life Sciences, Lanzhou University, Lanzhou 730000, Gansu Province, PR China; Department of Occupational and Environmental Health, School of Public Health, Lanzhou University, Lanzhou 730000, Gansu, PR China
| | - Yanrui Bai
- School of Life Sciences, Lanzhou University, Lanzhou 730000, Gansu Province, PR China
| | - Muhammad Usman
- School of Life Sciences, Lanzhou University, Lanzhou 730000, Gansu Province, PR China; Department of Occupational and Environmental Health, School of Public Health, Lanzhou University, Lanzhou 730000, Gansu, PR China
| | - Mohammed Jalalah
- Promising Center for Sensors and Electronic Devices (PCSED) Najran University, Najran 11001, Saudi Arabia
| | - Farid A Harraz
- Promising Center for Sensors and Electronic Devices (PCSED) Najran University, Najran 11001, Saudi Arabia; Nanomaterials and Nanotechnology Department, Central Metallurgical Research and Development Institute (CMRDI), P.O. 87 Helwan, Cairo 11421, Egypt
| | - M S Al-Assiri
- Promising Center for Sensors and Electronic Devices (PCSED) Najran University, Najran 11001, Saudi Arabia
| | - Xiangkai Li
- School of Life Sciences, Lanzhou University, Lanzhou 730000, Gansu Province, PR China
| | - El-Sayed Salama
- Department of Occupational and Environmental Health, School of Public Health, Lanzhou University, Lanzhou 730000, Gansu, PR China
| | - Chunjiang Zhang
- School of Life Sciences, Lanzhou University, Lanzhou 730000, Gansu Province, PR China.
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21
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Butler T, Kapoore RV, Vaidyanathan S. Phaeodactylum tricornutum: A Diatom Cell Factory. Trends Biotechnol 2020; 38:606-622. [PMID: 31980300 DOI: 10.1016/j.tibtech.2019.12.023] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 12/17/2019] [Accepted: 12/18/2019] [Indexed: 01/12/2023]
Abstract
A switch from a petroleum-based to a biobased economy requires the capacity to produce both high-value low-volume and low-value high-volume products. Recent evidence supports the development of microalgae-based microbial cell factories with the objective of establishing environmentally sustainable manufacturing solutions. Diatoms display rich diversity and potential in this regard. We focus on Phaeodactylum tricornutum, a pennate diatom that is commonly found in marine ecosystems, and discuss recent trends in developing the diatom chassis for the production of a suite of natural and genetically engineered products. Both upstream and downstream developments are reviewed for the commercial development of P. tricornutum as a cell factory for a spectrum of marketable products.
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Affiliation(s)
- Thomas Butler
- Department of Chemical and Biological Engineering, The University of Sheffield, Sheffield, S1 3JD, UK
| | - Rahul Vijay Kapoore
- Department of Chemical and Biological Engineering, The University of Sheffield, Sheffield, S1 3JD, UK; Present address: Department of Biosciences, College of Science, Swansea University, Swansea, SA2 8PP, UK
| | - Seetharaman Vaidyanathan
- Department of Chemical and Biological Engineering, The University of Sheffield, Sheffield, S1 3JD, UK.
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22
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Yunus IS, Palma A, Trudeau DL, Tawfik DS, Jones PR. Methanol-free biosynthesis of fatty acid methyl ester (FAME) in Synechocystis sp. PCC 6803. Metab Eng 2020; 57:217-227. [DOI: 10.1016/j.ymben.2019.12.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 12/01/2019] [Accepted: 12/04/2019] [Indexed: 12/11/2022]
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23
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Ren L, Sun X, Zhang L, Zhao Q, Huang H. Identification of active pathways of Chlorella protothecoides by elementary mode analysis integrated with fluxomic data. ALGAL RES 2020. [DOI: 10.1016/j.algal.2019.101767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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24
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Park S, Nguyen THT, Jin E. Improving lipid production by strain development in microalgae: Strategies, challenges and perspectives. BIORESOURCE TECHNOLOGY 2019; 292:121953. [PMID: 31405625 DOI: 10.1016/j.biortech.2019.121953] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/31/2019] [Accepted: 08/01/2019] [Indexed: 05/16/2023]
Abstract
Over the past decade, the number of original articles and reviews presenting microalgae as a promising feedstock for biodiesel has increased tremendously. Many improvements of microalgae have been achieved through selection and strain development for industrial applications. However, the large-scale production of lipids for commercialization is not yet realistic because the production is still much more expensive than that of agricultural products. This review summarizes recent research on the induction of lipid biosynthesis in microalgae and the various strategies of genetic and metabolic engineering for enhancing lipid production. Strain engineering targets are proposed based on these strategies. To address current limitations of strain engineering for lipid production, this review provides insights on recent engineering strategies based on molecular tools and methods, and also discusses further perspectives.
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Affiliation(s)
- Seunghye Park
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, Republic of Korea
| | - Thu Ha Thi Nguyen
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, Republic of Korea
| | - EonSeon Jin
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, Republic of Korea.
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25
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Cheng D, Li X, Yuan Y, Zhao Q. Kinetic model for effects of simulated flue gas onto growth profiles of Chlorella sp. AE10 and Chlorella sp. Cv. Biotechnol Appl Biochem 2019; 67:783-789. [PMID: 31584216 DOI: 10.1002/bab.1829] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 09/22/2019] [Indexed: 11/11/2022]
Abstract
Microalgae are potential candidate for biofuel production as alternative one for fossil fuels. CO2 in flue gas is available carbon source to support microalgae growth. In this study, the effects of different concentrations of the simulated flue gas onto algal growth and photosynthetic activity were evaluated for both Chlorella sp. AE10 and Chlorella sp. Cv. The growth profiles were correlated by a simple kinetic model. It was indicated that the simulated flue gas led to low pH and the photosynthetic activity was partially destroyed. Chlorella sp. Cv can tolerate full simulated flue gas, 10% CO2 + 200 ppm NOx + 100 ppm SOx . The pH in medium maintained at 6 and the photosynthetic activity was more than 0.6 at the first 6 days. If the concentration of NOx was more 100 ppm and that of SOx was more than 50 ppm, the pH was declined to 4 at day 2 or 3 for Chlorella sp. AE10. At the same time, the related photosynthetic activities of Chlorella sp. AE10 were less than 0.4, which was not suitable for algal growth. It was shown that Chlorella sp. Cv could be used for CO2 fixation from the simulated flue gas.
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Affiliation(s)
- Dujia Cheng
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, People's Republic of China.,University of Chinese Academy of Sciences, Beijing, People's Republic of China.,ShanghaiTech University, Shanghai, People's Republic of China
| | - Xuyang Li
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, People's Republic of China.,School of Life Science, Shanghai University, Shanghai, People's Republic of China
| | - Yizhong Yuan
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, People's Republic of China.,University of Chinese Academy of Sciences, Beijing, People's Republic of China.,ShanghaiTech University, Shanghai, People's Republic of China
| | - Quanyu Zhao
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, People's Republic of China.,ShanghaiTech University, Shanghai, People's Republic of China.,School of Pharmaceutical Science, Nanjing Tech University, Nanjing, People's Republic of China
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26
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Overexpression of malic enzyme isoform 2 in Chlamydomonas reinhardtii PTS42 increases lipid production. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biteb.2019.100239] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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27
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Teco-Bravo JI, Barahona-Pérez LF, Reyes-Sosa CF, Ku-González ÁF, Herrera-Valencia VA, Peraza-Echeverria S. Enhanced production of triacylglycerols and polyunsaturated fatty acids in novel acid-tolerant mutants of the green microalga Chlorella saccharophila. Bioprocess Biosyst Eng 2019; 42:1561-1571. [PMID: 31187270 DOI: 10.1007/s00449-019-02153-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 04/18/2019] [Accepted: 05/25/2019] [Indexed: 11/25/2022]
Abstract
In this study, the microalga Chlorella saccharophila was subjected to ultraviolet (UV) mutagenesis, and mutant screening was conducted based on acidity tolerance to generate mutants with increased triacylglycerol (TAG) and polyunsaturated fatty acid (PUFA) contents. Two improved mutant strains (M1 and M5) were generated. M1 and M5 accumulated 27.2% and 27.4% more TAG, respectively, and showed stronger fluorescence intensity than the wild-type (WT) strain when the cells of these mutants were stained with the lipophilic Nile Red stain. In the M1 mutant, 50.5% of the fatty acid methyl esters (FAMEs) were saturated (C16:0 and C18:0) and 25.27% were monounsaturated (C18:1) fatty acids which are suitable for biofuels production. In the M5 mutant, 65.19% of the total FAMEs were nutritional PUFAs (C16:2, C18:2, and C18:3), while these FAMEs were not detected in the WT. These results demonstrated that UV mutagenesis coupled to an acid pH screening strategy represents a valuable and fast platform to generate mutants of C. saccharophila with improved TAG and PUFA contents for biofuels and nutraceutical applications, respectively.
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Affiliation(s)
- Jalsen Iván Teco-Bravo
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán (CICY), Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, C.P. 97205, Mérida, Yucatán, México
| | - Luis Felipe Barahona-Pérez
- Unidad de Energía Renovable, Centro de Investigación Científica de Yucatán (CICY), Carretera Sierra Papacal-Chuburná Puerto, km 5. Sierra Papacal, C.P. 97302, Mérida, Yucatán, México
| | - Carlos Francisco Reyes-Sosa
- Departamento de Ingeniería Química y Bioquímica, Tecnológico Nacional de México, Instituto Tecnológico de Mérida, Avenida Tecnológico S/N, C.P. 97118, Mérida, Yucatán, México
| | - Ángela Francisca Ku-González
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán (CICY), Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, C.P. 97205, Mérida, Yucatán, México
| | - Virginia Aurora Herrera-Valencia
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán (CICY), Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, C.P. 97205, Mérida, Yucatán, México.
| | - Santy Peraza-Echeverria
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán (CICY), Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, C.P. 97205, Mérida, Yucatán, México.
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28
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Economic feasibility and long-term sustainability criteria on the path to enable a transition from fossil fuels to biofuels. Curr Opin Biotechnol 2019; 57:175-182. [DOI: 10.1016/j.copbio.2019.04.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 03/31/2019] [Accepted: 04/16/2019] [Indexed: 12/19/2022]
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29
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Yan Q, Pfleger BF. Revisiting metabolic engineering strategies for microbial synthesis of oleochemicals. Metab Eng 2019; 58:35-46. [PMID: 31022535 DOI: 10.1016/j.ymben.2019.04.009] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/20/2019] [Accepted: 04/21/2019] [Indexed: 02/06/2023]
Abstract
Microbial production of oleochemicals from renewable feedstocks remains an attractive route to produce high-energy density, liquid transportation fuels and high-value chemical products. Metabolic engineering strategies have been applied to demonstrate production of a wide range of oleochemicals, including free fatty acids, fatty alcohols, esters, olefins, alkanes, ketones, and polyesters in both bacteria and yeast. The majority of these demonstrations synthesized products containing long-chain fatty acids. These successes motivated additional effort to produce analogous molecules comprised of medium-chain fatty acids, molecules that are less common in natural oils and therefore of higher commercial value. Substantial progress has been made towards producing a subset of these chemicals, but significant work remains for most. The other primary challenge to producing oleochemicals in microbes is improving the performance, in terms of yield, rate, and titer, of biocatalysts such that economic large-scale processes are feasible. Common metabolic engineering strategies include blocking pathways that compete with synthesis of oleochemical building blocks and/or consume products, pulling flux through pathways by removing regulatory signals, pushing flux into biosynthesis by overexpressing rate-limiting enzymes, and engineering cells to tolerate the presence of oleochemical products. In this review, we describe the basic fundamentals of oleochemical synthesis and summarize advances since 2013 towards improving performance of heterotrophic microbial cell factories.
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Affiliation(s)
- Qiang Yan
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Brian F Pfleger
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Wisconsin-Madison, Madison, WI 53706, United States; Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI 53706, United States.
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30
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Muñoz CF, Weusthuis RA, D’Adamo S, Wijffels RH. Effect of Single and Combined Expression of Lysophosphatidic Acid Acyltransferase, Glycerol-3-Phosphate Acyltransferase, and Diacylglycerol Acyltransferase on Lipid Accumulation and Composition in Neochloris oleoabundans. FRONTIERS IN PLANT SCIENCE 2019; 10:1573. [PMID: 31850043 PMCID: PMC6895027 DOI: 10.3389/fpls.2019.01573] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 11/11/2019] [Indexed: 05/03/2023]
Abstract
Microalgal lipids are promising feedstocks for food and biofuels. Since lipid production by microalgae is not yet economically feasible, genetic engineering is becoming a promising strategy to achieve higher lipid accumulation and productivities. Enzymes involved in the Kennedy pathway such as glycerol-3-phosphate acyltransferase (GPAT), lysophosphatidic acid acyltransferase (LPAT), and diacylglycerol acyltransferase (DGAT) catalyze key steps in the formation of triacylglycerol, which is the main constituent of lipids in N. oleoabundans. The overexpression of these enzymes in the targeted strain has a great potential to further increase their triacylglycerol content. We overexpressed single and multiple encoding genes for LPAT, GPAT, and DGAT from Acutodesmus obliquus in N. oleoabundans. Strains overexpressing single genes produced up to 52% and 45% g · gDW-1, which corresponds to 1.3- and 1.4-fold increase in total fatty acids and triacylglycerols, respectively. The orchestrated expression of the three genes resulted in 49% and 39% g · gDW-1, which is 1.2-folds increase in total fatty acids and triacylglycerols. Single expression of LPAT, GPAT, and DGAT genes resulted in higher lipid productivities during starvation without a significant effect on growth and photosynthetic activity during replete conditions. On the other hand, the simultaneous expression of LPAT, GPAT, and DGAT genes resulted in 52% lower growth rate, 14% lower photosynthetic activity and 4-folds increase in cell diameter. Moreover, the multigene expressing line showed a decrease in carbohydrates and protein content and an increase in pigments during nitrogen starved condition. The single and multiple expression of heterologous genes LPAT, GPAT, and DGAT showed to significantly enhanced the lipid accumulation in N. oleoabundans. Single gene expression resulted in higher lipid production and productivities without having a significant impact in the physiological status of the strains. This approach shows the potential for the generation of microalgal strains with higher economical potential for the production of lipids.
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Affiliation(s)
- Camilo F. Muñoz
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands
- *Correspondence: Camilo F. Muñoz,
| | - Ruud A. Weusthuis
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands
| | - Sarah D’Adamo
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands
| | - René H. Wijffels
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands
- Biosciences and Aquaculture, Nord University, Bodø, Norway
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He Q, Yang H, Hu C. Effects of temperature and its combination with high light intensity on lipid production of Monoraphidium dybowskii Y2 from semi-arid desert areas. BIORESOURCE TECHNOLOGY 2018; 265:407-414. [PMID: 29933188 DOI: 10.1016/j.biortech.2018.06.044] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 06/12/2018] [Accepted: 06/13/2018] [Indexed: 06/08/2023]
Abstract
Temperature and light intensity are important environmental factors influencing microalgae for biodiesel production. The aim of present work was to study the effects of temperature (15 °C, 25 °C, and 35 °C) and its combination with high light intensity (HL, 400 μmol photon m-2 s-1) on lipid production of Monoraphidium dybowskii Y2 which was isolated from desert. The results demonstrated that algal growth was only inhibited at 15 °C. Promoted lipid content and decreased Fv/Fm were observed in 15 °C and 35 °C. Cellular carbohydrate, protein conversion and membrane lipid (MGDG, DGDG and SQDG) remodeling contributes for lipid accumulation. Stress combined temperatures with HL are benefit for lipid production, especially desired neutral lipid productivity all exceed 40 mg L-1 d-1. Fatty acids compositions of C16:0 and C18:1 were further promoted under 15 °C or 35 °C combined with HL. Thus, M. dybowskii Y2 will well-adapted to outdoors cultivation for biodiesel production.
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Affiliation(s)
- Qiaoning He
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China
| | - Haijian Yang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Chunxiang Hu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
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Prospecting for Oleaginous and Robust Chlorella spp. for Coal-Fired Flue-Gas-Mediated Biodiesel Production. ENERGIES 2018. [DOI: 10.3390/en11082026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Prospecting for robust and high-productivity strains is a strategically important step in the microalgal biodiesel process. In this study, 30 local strains of Chlorella were evaluated in photobioreactors for biodiesel production using coal-fired flue-gas. Three strains (M082, M134, and KR-1) were sequentially selected based on cell growth, lipid content, and fatty acid composition under autotrophic and mixotrophic conditions. Under autotrophic conditions, M082 and M134 showed comparable lipid contents (ca. 230 mg FAME [fatty acid methyl esters derived from microalgal lipids]/g cell) and productivities (ca. 40 mg FAME/L·d) versus a reference strain (KR-1) outdoors with actual flue-gas (CO2, 13%). Interestingly, under mixotrophic conditions, M082 demonstrated, along with maximal lipid content (397 mg FAME/g cell), good tolerance to high temperature (40 °C). Furthermore, the fatty acid methyl esters met important international standards under all of the tested culture conditions. Thus, it was concluded that M082 can be a feedstock of choice for coal-fired, flue-gas-mediated biodiesel production.
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Wang X, Dong HP, Wei W, Balamurugan S, Yang WD, Liu JS, Li HY. Dual expression of plastidial GPAT1 and LPAT1 regulates triacylglycerol production and the fatty acid profile in Phaeodactylum tricornutum. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:318. [PMID: 30479663 PMCID: PMC6249879 DOI: 10.1186/s13068-018-1317-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 11/13/2018] [Indexed: 05/03/2023]
Abstract
BACKGROUND Metabolic engineering has emerged as a potential strategy for improving microalgal lipid content through targeted changes to lipid metabolic networks. However, the intricate nature of lipogenesis has impeded metabolic engineering. Therefore, it is very important to identify the crucial metabolic nodes and develop strategies to exploit multiple genes for transgenesis. In an attempt to unravel the microalgal triacylglycerol (TAG) pathway, we overexpressed two key lipogenic genes, glycerol-3-phosphate acyltransferase (GPAT1) and lysophosphatidic acid acyltransferase (LPAT1), in oleaginous Phaeodactylum tricornutum and determined their roles in microalgal lipogenesis. RESULTS Engineered P. tricornutum strains showed enhanced growth and photosynthetic efficiency compared with that of the wild-type during the growth phase of the cultivation period. However, both the cell types reached stationary phase on day 7. Overexpression of GPAT1 and LPAT1 increased the TAG content by 2.3-fold under nitrogen-replete conditions without compromising cell growth, and they also orchestrated the expression of other key genes involved in TAG synthesis. The transgenic expression of GPAT1 and LPAT1 influenced the expression of malic enzyme and glucose 6-phosphate dehydrogenase, which enhanced the levels of lipogenic NADPH in the transgenic lines. In addition, GPAT1 and LPAT1 preferred C16 over C18 at the sn-2 position of the glycerol backbone. CONCLUSION Overexpression of GPAT1 together with LPAT1 significantly enhanced lipid content without affecting growth and photosynthetic efficiency, and they orchestrated the expression of other key photosynthetic and lipogenic genes. The lipid profile for elevated fatty acid content (C16-CoA) demonstrated the involvement of the prokaryotic TAG pathway in marine diatoms. The results suggested that engineering dual metabolic nodes should be possible in microalgal lipid metabolism. This study also provides the first demonstration of the role of the prokaryotic TAG biosynthetic pathway in lipid overproduction and indicates that the fatty acid profile can be tailored to improve lipid production.
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Affiliation(s)
- Xiang Wang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
| | - Hong-Po Dong
- School of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, 524088 China
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200062 China
| | - Wei Wei
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
| | - Srinivasan Balamurugan
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
| | - Wei-Dong Yang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
| | - Jie-Sheng Liu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
| | - Hong-Ye Li
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
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