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Ji X, Chen L, Yang G, Tang C, Zhou W, Liu T, Lu X. Mutagenesis and fluorescence-activated cell sorting of oleaginous Saccharomyces cerevisiae and the multi-omics analysis of its high lipid accumulation mechanisms. BIORESOURCE TECHNOLOGY 2024; 406:131062. [PMID: 38964514 DOI: 10.1016/j.biortech.2024.131062] [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: 04/15/2024] [Revised: 06/14/2024] [Accepted: 07/01/2024] [Indexed: 07/06/2024]
Abstract
Acquiring lipid-producing strains of Saccharomyces cerevisiae is necessary for producing high-value palmitoleic acid. This study sought to generate oleaginous S. cerevisiae mutants through a combination of zeocin mutagenesis and fluorescence-activated cell sorting, and then to identify key mutations responsible for enhanced lipid accumulation by multi-omics sequencing. Following three consecutive rounds of mutagenesis and sorting, a mutant, MU310, with the lipid content of 44%, was successfully obtained. Transcriptome and targeted metabolome analyses revealed that a coordinated response involving fatty acid precursor biosynthesis, nitrogen metabolism, pentose phosphate pathway, ethanol conversion, amino acid metabolism and fatty acid β-oxidation was crucial for promoting lipid accumulation. The carbon fluxes of acetyl-CoA and NADPH in lipid biosynthesis were boosted in these pathways. Certain transcriptional regulators may also play significant roles in modulating lipid biosynthesis. Results of this study provide high-quality resource for palmitoleic acid production and deepen the understanding of lipid synthesis in yeast.
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Affiliation(s)
- Xiaotong Ji
- Key Laboratory of Biofuels, Key Laboratory of Shandong Energy Biological Genetic Resources, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao 266101, China; Shandong Energy Institute, Songling Rd 189, Qingdao 266101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lin Chen
- Key Laboratory of Biofuels, Key Laboratory of Shandong Energy Biological Genetic Resources, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao 266101, China; Shandong Energy Institute, Songling Rd 189, Qingdao 266101, China
| | - Guanpin Yang
- College of Marine Life Sciences, Ocean University of China, Songling Rd 238, Qingdao 266100, China
| | - Chunlei Tang
- Key Laboratory of Biofuels, Key Laboratory of Shandong Energy Biological Genetic Resources, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao 266101, China; Shandong Energy Institute, Songling Rd 189, Qingdao 266101, China
| | - Wenjun Zhou
- Key Laboratory of Biofuels, Key Laboratory of Shandong Energy Biological Genetic Resources, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao 266101, China; Shandong Energy Institute, Songling Rd 189, Qingdao 266101, China.
| | - Tianzhong Liu
- Key Laboratory of Biofuels, Key Laboratory of Shandong Energy Biological Genetic Resources, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao 266101, China; Shandong Energy Institute, Songling Rd 189, Qingdao 266101, China.
| | - Xuefeng Lu
- Key Laboratory of Biofuels, Key Laboratory of Shandong Energy Biological Genetic Resources, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao 266101, China; Shandong Energy Institute, Songling Rd 189, Qingdao 266101, China
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Hassanien A, Saadaoui I, Schipper K, Al-Marri S, Dalgamouni T, Aouida M, Saeed S, Al-Jabri HM. Genetic engineering to enhance microalgal-based produced water treatment with emphasis on CRISPR/Cas9: A review. Front Bioeng Biotechnol 2023; 10:1104914. [PMID: 36714622 PMCID: PMC9881887 DOI: 10.3389/fbioe.2022.1104914] [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: 11/22/2022] [Accepted: 12/30/2022] [Indexed: 01/15/2023] Open
Abstract
In recent years, the increased demand for and regional variability of available water resources, along with sustainable water supply planning, have driven interest in the reuse of produced water. Reusing produced water can provide important economic, social, and environmental benefits, particularly in water-scarce regions. Therefore, efficient wastewater treatment is a crucial step prior to reuse to meet the requirements for use within the oil and gas industry or by external users. Bioremediation using microalgae has received increased interest as a method for produced water treatment for removing not only major contaminants such as nitrogen and phosphorus, but also heavy metals and hydrocarbons. Some research publications reported nearly 100% removal of total hydrocarbons, total nitrogen, ammonium nitrogen, and iron when using microalgae to treat produced water. Enhancing microalgal removal efficiency as well as growth rate, in the presence of such relevant contaminants is of great interest to many industries to further optimize the process. One novel approach to further enhancing algal capabilities and phytoremediation of wastewater is genetic modification. A comprehensive description of using genetically engineered microalgae for wastewater bioremediation is discussed in this review. This article also reviews random and targeted mutations as a method to alter microalgal traits to produce strains capable of tolerating various stressors related to wastewater. Other methods of genetic engineering are discussed, with sympathy for CRISPR/Cas9 technology. This is accompanied by the opportunities, as well as the challenges of using genetically engineered microalgae for this purpose.
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Affiliation(s)
- Alaa Hassanien
- Algal Technologies Program, Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha, Qatar
| | - Imen Saadaoui
- Algal Technologies Program, Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha, Qatar,Biological and environmental Sciences Department, College of Arts and Sciences, Qatar University, Doha, Qatar
| | - Kira Schipper
- Algal Technologies Program, Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha, Qatar
| | | | - Tasneem Dalgamouni
- Algal Technologies Program, Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha, Qatar
| | - Mustapha Aouida
- Division of Biological and Biomedical Sciences, Qatar Foundation, College of Health and Life Sciences, Education City, Hamad Bin Khalifa University, Doha, Qatar
| | - Suhur Saeed
- ExxonMobil Research Qatar (EMRQ), Doha, Qatar
| | - Hareb M. Al-Jabri
- Algal Technologies Program, Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha, Qatar,Biological and environmental Sciences Department, College of Arts and Sciences, Qatar University, Doha, Qatar,*Correspondence: Hareb M. Al-Jabri,
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3
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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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Liu H, Yan N, Wong TY, Lam H, Lam JWY, Kwok RTK, Sun J, Tang BZ. Fluorescent Imaging and Sorting of High-Lipid-Content Strains of Green Algae by Using an Aggregation-Induced Emission Luminogen. ACS NANO 2022; 16:14973-14981. [PMID: 36099405 DOI: 10.1021/acsnano.2c05976] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Microalgae-based biofuels are receiving attention at the environmental, economic, and social levels because they are clean, renewable, and quickly produced. The green algae Chlorella vulgaris has been extensively studied in research laboratories and the biofuel industry as a model organism to increase lipid production to be cost-effective in commercial production. In this work, we utilized a lipid-droplet-specific luminogen with aggregation-induced emission (AIE) characteristics to increase the lipid production of C. vulgaris by fluorescent imaging and sorting of those algal cells with large and rich lipid droplets for subculturing. The AIE-active TPA-A enabled real-time monitoring of the size and number of lipid droplets in C. vulgaris during their growth period so that we can identify the best time for harvesting. Furthermore, the algae cells with high lipid content were identified and collected for subculturing by the technique of fluorescence-activated cell sorting (FACS). The lipid production in the generation of two successive selections was almost doubled compared to the generation with natural selection. This work demonstrated that the technologies of AIE and FACS could be applied together to improve the production of a third-generation biofuel.
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Affiliation(s)
- Haixiang Liu
- HKUST-Shenzhen Research Institute, No. 9 Yuexing 1st Rd, South Area, Hi-tech Park, Nanshan, Shenzhen 518057, China
| | - Neng Yan
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Tin Yan Wong
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Henry Lam
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Jacky W Y Lam
- HKUST-Shenzhen Research Institute, No. 9 Yuexing 1st Rd, South Area, Hi-tech Park, Nanshan, Shenzhen 518057, China
- The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Ryan T K Kwok
- HKUST-Shenzhen Research Institute, No. 9 Yuexing 1st Rd, South Area, Hi-tech Park, Nanshan, Shenzhen 518057, China
- The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Jianwei Sun
- The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Ben Zhong Tang
- HKUST-Shenzhen Research Institute, No. 9 Yuexing 1st Rd, South Area, Hi-tech Park, Nanshan, Shenzhen 518057, China
- The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
- School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China
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Rearte T, Rodriguez N, Sabatté F, Fabrizio de Iorio A. Unicellular microalgae vs. filamentous algae for wastewater treatment and nutrient recovery. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102442] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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7
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Gao F, Cabanelas ITD, Wijffels RH, Barbosa MJ. Fucoxanthin and docosahexaenoic acid production by cold-adapted Tisochrysis lutea. N Biotechnol 2021; 66:16-24. [PMID: 34500104 DOI: 10.1016/j.nbt.2021.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 11/30/2022]
Abstract
Tisochrysis lutea is an important microalgal species for fucoxanthin and docosahexaenoic acid (DHA) production with an optimum cultivation temperature of approximately 30 °C. The aim of the present work was to develop a winter strain with high productivity at 15 °C. The response of the original strain to a decrease in temperature from 30 °C to 15 °C was investigated in continuous turbidostat experiments. This was followed by adaptation for >180 days at 15 °C and 2 rounds of sorting for cells with high chlorophyll fluorescence (top 5%) using fluorescence-activated cell sorting (FACS). For the original strain the productivity of biomass, fucoxanthin, and DHA decreased by 92 %, 98 % and 85 % respectively when decreasing the temperature from 30 °C to 15 °C. In the sorted cold-adapted 'winter strain', biomass, fucoxanthin, and DHA productivities were similar to those at 30 °C. In addition, the fucoxanthin concentration increased from 1.11 to 4.24 mg g-1 dry weight and the polar lipid fraction in total fatty acids increased from 21 % to 55 %. The winter strain showed a robust and stable phenotype after one year of cultivation, expanding the outdoor fucoxanthin and lipid production seasons for this species.
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Affiliation(s)
- Fengzheng Gao
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA, Wageningen, Netherlands.
| | | | - René H Wijffels
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA, Wageningen, Netherlands; Faculty Biosciences and Aquaculture, Nord University, N-8049, Bodø, Norway.
| | - Maria J Barbosa
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA, Wageningen, Netherlands.
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Reza AHMM, Zhou Y, Qin J, Tang Y. Aggregation-induced emission luminogens for lipid droplet imaging. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 184:101-144. [PMID: 34749970 DOI: 10.1016/bs.pmbts.2021.06.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Lipid droplets (LDs) are evolutionarily conserved organelles involved in energy homeostasis and versatile intracellular processes in different cell types. Their importance is ubiquitous, ranges from utilization as the biofunctional components to third-generation biofuel production from microalgae, while morphology and functional perturbations could also relate to the multiple diseases in higher mammals. Biosynthesis of lipids can be triggered by multiple factors related to organismal physiology and the surrounding environment. An early prediction of this might help take necessary actions toward desired outcomes. In vivo visualization of LDs can give molecular insight into regulatory mechanisms and the underlying connections with other cellular structures. Traditional bioprobes for LDs detection often suffer from different dye-specific limitations such as aggregation-caused quenching and self-decomposition phenomena that hinder the research advancement. The emergence of lipid-specific nanoprobes with aggregation-induced emission (AIE) attributes in recent years is promising in remunerative characteristics with defined bioimaging properties. By utilizing the easy synthetic techniques and exploiting the unique physical features of these molecules, highly selective, stable, biocompatible and facile fluorescent probes could be fabricated for lipid detection. This chapter will provide up-to-date insight into the recent advances in lipid-specific AIE-based probes to enhance the opportunities for basic research related to the distinct roles of LDs in living organisms.
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Affiliation(s)
- A H M Mohsinul Reza
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia; Institute for NanoScale Science and Technology, College of Science and Engineering, Flinders University, Adelaide, SA, Australia
| | - Yabin Zhou
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia
| | - Jianguang Qin
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia.
| | - Youhong Tang
- College of Science and Engineering, Flinders University, Adelaide, SA, Australia; Institute for NanoScale Science and Technology, College of Science and Engineering, Flinders University, Adelaide, SA, Australia.
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High-throughput insertional mutagenesis reveals novel targets for enhancing lipid accumulation in Nannochloropsis oceanica. Metab Eng 2021; 66:239-258. [PMID: 33971293 DOI: 10.1016/j.ymben.2021.04.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/07/2021] [Accepted: 04/18/2021] [Indexed: 12/17/2022]
Abstract
The microalga Nannochloropsis oceanica is considered a promising platform for the sustainable production of high-value lipids and biofuel feedstocks. However, current lipid yields of N. oceanica are too low for economic feasibility. Gaining fundamental insights into the lipid metabolism of N. oceanica could open up various possibilities for the optimization of this species through genetic engineering. Therefore, the aim of this study was to discover novel genes associated with an elevated neutral lipid content. We constructed an insertional mutagenesis library of N. oceanica, selected high lipid mutants by five rounds of fluorescence-activated cell sorting, and identified disrupted genes using a novel implementation of a rapid genotyping procedure. One particularly promising mutant (HLM23) was disrupted in a putative APETALA2-like transcription factor gene. HLM23 showed a 40%-increased neutral lipid content, increased photosynthetic performance, and no growth impairment. Furthermore, transcriptome analysis revealed an upregulation of genes related to plastidial fatty acid biosynthesis, glycolysis and the Calvin-Benson-Bassham cycle in HLM23. Insights gained in this work can be used in future genetic engineering strategies for increased lipid productivity of Nannochloropsis.
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Enhancing carbohydrate repartitioning into lipid and carotenoid by disruption of microalgae starch debranching enzyme. Commun Biol 2021; 4:450. [PMID: 33837247 PMCID: PMC8035404 DOI: 10.1038/s42003-021-01976-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 03/11/2021] [Indexed: 02/01/2023] Open
Abstract
Light/dark cycling is an inherent condition of outdoor microalgae cultivation, but is often unfavorable for lipid accumulation. This study aims to identify promising targets for metabolic engineering of improved lipid accumulation under outdoor conditions. Consequently, the lipid-rich mutant Chlamydomonas sp. KOR1 was developed through light/dark-conditioned screening. During dark periods with depressed CO2 fixation, KOR1 shows rapid carbohydrate degradation together with increased lipid and carotenoid contents. KOR1 was subsequently characterized with extensive mutation of the ISA1 gene encoding a starch debranching enzyme (DBE). Dynamic time-course profiling and metabolomics reveal dramatic changes in KOR1 metabolism throughout light/dark cycles. During light periods, increased flux from CO2 through glycolytic intermediates is directly observed to accompany enhanced formation of small starch-like particles, which are then efficiently repartitioned in the next dark cycle. This study demonstrates that disruption of DBE can improve biofuel production under light/dark conditions, through accelerated carbohydrate repartitioning into lipid and carotenoid.
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Gao F, Sá M, Cabanelas ITD, Wijffels RH, Barbosa MJ. Improved fucoxanthin and docosahexaenoic acid productivities of a sorted self-settling Tisochrysis lutea phenotype at pilot scale. BIORESOURCE TECHNOLOGY 2021; 325:124725. [PMID: 33508680 DOI: 10.1016/j.biortech.2021.124725] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 06/12/2023]
Abstract
This work aimed to select a Tisochrysis lutea phenotype with higher biomass and fucoxanthin productivities using fluorescence-activated cell sorting (FACS). A novel phenotype was obtained after 2 rounds of selection, based on high-fucoxanthin fluorescence. The resulting phenotype forms cell aggregates, has no flagella, and was stable after 15 months. Optimal temperature (30 °C) and light (300 µmol m-2 s-1) were obtained at laboratory scale, identical to the original strain. The biomass productivity was higher than the original strain: 1.9× at laboratory scale (0.4 L), and 4.5× under outdoor conditions (190 L). Moreover, compared to the original strain, the productivity of fucoxanthin increased 1.6-3.1× and docosahexaenoic acid 1.5-1.9×. These are the highest ever reported outdoor productivities, obtained with a robust new phenotype from a T. lutea monoculture isolated with FACS without genetic manipulation. The resulting phenotype shows high potential for industrial production.
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Affiliation(s)
- Fengzheng Gao
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands.
| | - Marta Sá
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands
| | | | - René H Wijffels
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands; Faculty Biosciences and Aquaculture, Nord University, N-8049 Bodø, Norway
| | - Maria J Barbosa
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands
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12
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Gao F, Woolschot S, Cabanelas ITD, Wijffels RH, Barbosa MJ. Light spectra as triggers for sorting improved strains of Tisochrysis lutea. BIORESOURCE TECHNOLOGY 2021; 321:124434. [PMID: 33257166 DOI: 10.1016/j.biortech.2020.124434] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 11/15/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
It is known that microalgae respond to different light colors, but not at single-cell level. This work aimed to assess if different light colors could be used as triggers to sort over-producing cells. Six light spectra were used: red + green + blue (RGBL), blue (BL), red (RL), green (GL), blue + red (BRL) and blue + green (BGL). Fluorescence-activated cell sorting method was used to analyse single-cell fluorescence and sort cells. BGL and RGBL lead to the highest fucoxanthin production, while RL showed the lowest. Therefore, it was hypothesized that hyper-producing cells can be isolated efficiently under the adverse condition (RL). After exposure to all light colors for 14 days, the top 1% fucoxanthin producing cells were sorted. A sorted strain from RL showed higher (16-19%) growth rate and fucoxanthin productivity. This study showed how light spectra affected single-cell fucoxanthin and lipid contents and productivities. Also, it supplied an approach to sort for high-fucoxanthin or high-lipid cells.
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Affiliation(s)
- Fengzheng Gao
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands.
| | - Sep Woolschot
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands
| | | | - René H Wijffels
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands; Faculty Biosciences and Aquaculture, Nord University, N-8049 Bodø, Norway
| | - Maria J Barbosa
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands
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Gao F, Teles Cabanelas Itd I, Ferrer-Ledo N, Wijffels RH, Barbosa MJ. Production and high throughput quantification of fucoxanthin and lipids in Tisochrysis lutea using single-cell fluorescence. BIORESOURCE TECHNOLOGY 2020; 318:124104. [PMID: 32942095 DOI: 10.1016/j.biortech.2020.124104] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 08/31/2020] [Accepted: 09/03/2020] [Indexed: 05/12/2023]
Abstract
This work aimed to investigate the accumulation of fucoxanthin and lipids in Tisochrysis lutea during growth (N+) and nitrogen-starvation (N-) and to correlate these products with single-cell emissions using fluorescence-activated cell sorting (FACS). Fucoxanthin content decreased 52.94% from N+ to N- in batch cultivation; increased 40.53% as dilution rate changed from 0.16 to 0.55 d-1 in continuous cultivation. Total lipids (N-) were constant (~250 mg/g), but the abundance of neutral lipids increased from 4.87% to 40.63%. Nile red can stain both polar and neutral lipids. However, in vivo, this differentiation is limited due to an overlapping of signals between 600 and 660 nm, caused by neutral lipids concentrations above 3.48% (W/W). Chlorophyll autofluorescence (720 nm) was reported for the first time as a proxy for fucoxanthin (R2 = 0.90) and polar lipids (R2 = 0.98). FACS can be used in high throughput quantification of pigments and lipids and to select and sort cells with high-fucoxanthin/lipids.
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Affiliation(s)
- Fengzheng Gao
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands.
| | - Iago Teles Cabanelas Itd
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands
| | - Narcís Ferrer-Ledo
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands
| | - René H Wijffels
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands; Faculty Biosciences and Aquaculture, Nord University, N-8049 Bodø, Norway
| | - Maria J Barbosa
- Wageningen University, Bioprocess Engineering, AlgaePARC, P.O. Box 16, 6700 AA Wageningen, Netherlands
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Improving ‘Lipid Productivity’ in Microalgae by Bilateral Enhancement of Biomass and Lipid Contents: A Review. SUSTAINABILITY 2020. [DOI: 10.3390/su12219083] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Microalgae have received widespread interest owing to their potential in biofuel production. However, economical microalgal biomass production is conditioned by enhancing the lipid accumulation without decreasing growth rate or by increasing both simultaneously. While extensive investigation has been performed on promoting the economic feasibility of microalgal-based biofuel production that aims to increase the productivity of microalgae species, only a handful of them deal with increasing lipid productivity (based on lipid contents and growth rate) in the feedstock production process. The purpose of this review is to provide an overview of the recent advances and novel approaches in promoting lipid productivity (depends on biomass and lipid contents) in feedstock production from strain selection to after-harvesting stages. The current study comprises two parts. In the first part, bilateral improving biomass/lipid production will be investigated in upstream measures, including strain selection, genetic engineering, and cultivation stages. In the second part, the enhancement of lipid productivity will be discussed in the downstream measure included in the harvesting and after-harvesting stages. An integrated approach involving the strategies for increasing lipid productivity in up- and down-stream measures can be a breakthrough approach that would promote the commercialization of market-driven microalgae-derived biofuel production.
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Abstract
The staining of lipids in algae cells with BODIPY dyes is much less studied compared to Nile red; therefore, a complex of issues concerning staining details and fluorescence measurements still should be clarified for the species that vary in cell wall complexity. Nevertheless, some general guidelines could be given, and a preliminary protocol of the method is provided based on the existing data. The semiquantification of lipid could be reliable if the staining protocol will be developed and adapted for particular microalgae species.
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Deka D, Marwein R, Chikkaputtaiah C, Kaki SS, Azmeera T, Boruah HPD, Velmurugan N. Strain improvement of long-chain fatty acids producing Micractinium sp. by flow cytometry. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.06.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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17
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Choi HI, Hwang SW, Sim SJ. Comprehensive approach to improving life-cycle CO 2 reduction efficiency of microalgal biorefineries: A review. BIORESOURCE TECHNOLOGY 2019; 291:121879. [PMID: 31377048 DOI: 10.1016/j.biortech.2019.121879] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/21/2019] [Accepted: 07/22/2019] [Indexed: 06/10/2023]
Abstract
Along with the increase in global awareness of rising CO2 levels, microalgae have attracted considerable interest as a promising CO2 reduction platforms since they exhibit outstanding biomass productivity and are capable of producing numerous valuable products. At this moment, however, two major barriers, relatively low photosynthetic CO2 fixation efficiency and necessity of carbon-intensive microalgal process, obstruct them to be practically utilized. This review suggests effective approaches to improve life-cycle CO2 reduction of microalgal biorefinery. In order to enhance photosynthetic CO2 fixation, strategies to augment carbon content and to increase biomass productivity should be considered. For reducing CO2 emissions associated with the process operations, introduction of efficient process elements, designing of energy-saving process routes, reuse of waste resources and utilization of process integration can be noteworthy options. These comprehensive strategies will provide guidance for microalgal biorefineries to become a practical CO2 reduction technology in near future.
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Affiliation(s)
- Hong Il Choi
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Sung-Won Hwang
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea.
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18
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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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19
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Suarez Garcia E, Lo C, Eppink M, Wijffels R, van den Berg C. Understanding mild cell disintegration of microalgae in bead mills for the release of biomolecules. Chem Eng Sci 2019. [DOI: 10.1016/j.ces.2019.04.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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20
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Gouveia JD, Lian J, Steinert G, Smidt H, Sipkema D, Wijffels RH, Barbosa MJ. Associated bacteria of Botryococcus braunii (Chlorophyta). PeerJ 2019; 7:e6610. [PMID: 30944776 PMCID: PMC6441321 DOI: 10.7717/peerj.6610] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 02/12/2019] [Indexed: 01/14/2023] Open
Abstract
Botryococcus braunii (Chlorophyta) is a green microalga known for producing hydrocarbons and exopolysaccharides (EPS). Improving the biomass productivity of B. braunii and hence, the productivity of the hydrocarbons and of the EPS, will make B. braunii more attractive for industries. Microalgae usually cohabit with bacteria which leads to the formation of species-specific communities with environmental and biological advantages. Bacteria have been found and identified with a few B. braunii strains, but little is known about the bacterial community across the different strains. A better knowledge of the bacterial community of B. braunii will help to optimize the biomass productivity, hydrocarbons, and EPS accumulation. To better understand the bacterial community diversity of B. braunii, we screened 12 strains from culture collections. Using 16S rRNA gene analysis by MiSeq we described the bacterial diversity across 12 B. braunii strains and identified possible shared communities. We found three bacterial families common to all strains: Rhizobiaceae, Bradyrhizobiaceae, and Comamonadaceae. Additionally, the results also suggest that each strain has its own specific bacteria that may be the result of long-term isolated culture.
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Affiliation(s)
- Joao D. Gouveia
- Bioprocess Engineering, Wageningen University & Research, Wageningen, The Netherlands
| | - Jie Lian
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands
| | - Georg Steinert
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands
| | - Hauke Smidt
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands
| | - Detmer Sipkema
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands
| | - Rene H. Wijffels
- Bioprocess Engineering, Wageningen University & Research, Wageningen, The Netherlands
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Maria J. Barbosa
- Bioprocess Engineering, Wageningen University & Research, Wageningen, The Netherlands
- Department of Biology, University of Bergen, Bergen, Norway
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21
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Janssen JH, Wijffels RH, Barbosa MJ. Lipid Production in Nannochloropsis gaditana during Nitrogen Starvation. BIOLOGY 2019; 8:biology8010005. [PMID: 30626148 PMCID: PMC6466408 DOI: 10.3390/biology8010005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 01/03/2019] [Indexed: 12/19/2022]
Abstract
The microalga Nannochloropsis gaditana is a natural producer of triacylglycerol (TAG) and the omega-3 fatty acid eicosapentaenoic acid (EPA). TAG accumulation is induced by nitrogen starvation. The biomass-specific photon supply rate used had an effect on EPA and TAG accumulation during nitrogen starvation as well as on the localization of EPA accumulation. Clear differences in TAG yield on light were found for different biomass-specific photon supply rates and light regimes during nitrogen starvation. De novo EPA synthesis or the translocation of EPA between lipid fractions might be limiting for EPA accumulation in TAG. Further studies are needed to fully understand EPA accumulation in TAG during nitrogen starvation. To elucidate the function of EPA in TAG nitrogen recovery, experiments are suggested. The overexpression of genes involved in de novo EPA synthesis and translocation is proposed to elucidate the exact metabolic routes involved in these processes during nitrogen starvation. This work addresses future opportunities to increase EPA accumulation.
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Affiliation(s)
- Jorijn H Janssen
- Bioprocess Engineering, AlgaePARC, Wageningen University and Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands.
| | - René H Wijffels
- Bioprocess Engineering, AlgaePARC, Wageningen University and Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands.
- Faculty of Biosciences and Aquaculture, Nord University, N-8049 Bodø, Norway.
| | - Maria J Barbosa
- Bioprocess Engineering, AlgaePARC, Wageningen University and Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands.
- Department of Biology, University of Bergen, P.O. Box 7803, 5006 Bergen, Norway.
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22
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Abstract
Microalgae have been used commercially since the 1950s and 1960s, particularly in the Far East for human health foods and in the United States for wastewater treatment. Initial attempts to produce bulk chemicals such as biofuels from microalgae were not successful, despite commercially favorable conditions during the 1970s oil crisis. However, research initiatives at this time, many using extremophilic microalgae and cyanobacteria (e.g., Dunaliella and Spirulina), did solve many problems and clearly identified biomass productivity and harvesting as the two main constraints stopping microalgae producing bulk chemicals, such as biofuels, on a large scale. In response to the growing unease around global warming, induced by anthropogenic CO2 emissions, microalgae were again suggested as a carbon neutral process to produce biofuels. This recent phase of microalgae biofuels research can be thought to have started around 2007, when a very highly cited review by Chisti was published. Since 2007, a large body of scientific publications have appeared on all aspects of microalgae biotechnology, but with a clear emphasis on neutral lipid (triacylglycerol) synthesis and the use of neutral lipids as precursors for biodiesel production. In this review, the key research on microalgal biotechnology that took place prior to 2007 will be summarized and then the research trends post 2007 will be examined emphasizing the research into producing biodiesel from microalgae.
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Affiliation(s)
- D James Gilmour
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom.
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23
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Can We Approach Theoretical Lipid Yields in Microalgae? Trends Biotechnol 2018; 36:265-276. [DOI: 10.1016/j.tibtech.2017.10.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 10/29/2017] [Accepted: 10/30/2017] [Indexed: 11/17/2022]
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24
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Pereira H, Schulze PS, Schüler LM, Santos T, Barreira L, Varela J. Fluorescence activated cell-sorting principles and applications in microalgal biotechnology. ALGAL RES 2018. [DOI: 10.1016/j.algal.2017.12.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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25
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Yuan Y, Liu H, Li X, Qi W, Cheng D, Tang T, Zhao Q, Wei W, Sun Y. Enhancing Carbohydrate Productivity of Chlorella sp. AE10 in Semi-continuous Cultivation and Unraveling the Mechanism by Flow Cytometry. Appl Biochem Biotechnol 2017; 185:419-433. [DOI: 10.1007/s12010-017-2667-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 11/17/2017] [Indexed: 11/24/2022]
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26
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27
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Ghosh A, Khanra S, Mondal M, Devi TI, Halder G, Tiwari O, Bhowmick TK, Gayen K. Biochemical characterization of microalgae collected from north east region of India advancing towards the algae-based commercial production. ASIA-PAC J CHEM ENG 2017. [DOI: 10.1002/apj.2114] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ashmita Ghosh
- Department of Chemical Engineering; NIT Agartala; Jirania West Tripura 799046 India
| | - Saumyakanti Khanra
- Department of Chemical Engineering; NIT Agartala; Jirania West Tripura 799046 India
| | - Madhumanti Mondal
- Department of Chemical Engineering; NIT Durgapur; Durgapur West Bengal 713209 India
| | | | - Gopinath Halder
- Department of Chemical Engineering; NIT Durgapur; Durgapur West Bengal 713209 India
| | - O.N. Tiwari
- Centre for Conservation and Utilization of Blue Green Algae; Division of Microbiology ICAR-Indian Agricultural Research Institute; New Delhi 110012 India
| | | | - Kalyan Gayen
- Department of Chemical Engineering; NIT Agartala; Jirania West Tripura 799046 India
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28
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Enhancement of Biomass and Lipid Productivities of Water Surface-Floating Microalgae by Chemical Mutagenesis. Mar Drugs 2017; 15:md15060151. [PMID: 28555001 PMCID: PMC5484101 DOI: 10.3390/md15060151] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 05/19/2017] [Accepted: 05/24/2017] [Indexed: 11/16/2022] Open
Abstract
Water surface-floating microalgae have great potential for biofuel applications due to the ease of the harvesting process, which is one of the most problematic steps in conventional microalgal biofuel production. We have collected promising water surface-floating microalgae and characterized their capacity for biomass and lipid production. In this study, we performed chemical mutagenesis of two water surface-floating microalgae to elevate productivity. Floating microalgal strains AVFF007 and FFG039 (tentatively identified as Botryosphaerella sp. and Chlorococcum sp., respectively) were exposed to ethyl methane sulfonate (EMS) or 1-methyl-3-nitro-1-nitrosoguanidine (MNNG), and pale green mutants (PMs) were obtained. The most promising FFG039 PM formed robust biofilms on the surface of the culture medium, similar to those formed by wild type strains, and it exhibited 1.7-fold and 1.9-fold higher biomass and lipid productivities than those of the wild type. This study indicates that the chemical mutation strategy improves the lipid productivity of water surface-floating microalgae without inhibiting biofilm formation and floating ability.
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29
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Remmers IM, Martens DE, Wijffels RH, Lamers PP. Dynamics of triacylglycerol and EPA production in Phaeodactylum tricornutum under nitrogen starvation at different light intensities. PLoS One 2017; 12:e0175630. [PMID: 28403203 PMCID: PMC5389818 DOI: 10.1371/journal.pone.0175630] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 03/29/2017] [Indexed: 01/02/2023] Open
Abstract
Lipid production in microalgae is highly dependent on the applied light intensity. However, for the EPA producing model-diatom Phaeodactylum tricornutum, clear consensus on the impact of incident light intensity on lipid productivity is still lacking. This study quantifies the impact of different incident light intensities on the biomass, TAG and EPA yield on light in nitrogen starved batch cultures of P. tricornutum. The maximum biomass concentration and maximum TAG and EPA contents were found to be independent of the applied light intensity. The lipid yield on light was reduced at elevated light intensities (>100 μmol m-2 s-1). The highest TAG yield on light (112 mg TAG molph-1) was found at the lowest light intensity tested (60 μmol m-2 s-1), which is still relatively low to values reported in literature for other algae. Furthermore, mass balance analysis showed that the EPA fraction in TAG may originate from photosynthetic membrane lipids.
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Affiliation(s)
- Ilse M. Remmers
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, Wageningen, The Netherlands
- * E-mail:
| | - Dirk E. Martens
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, Wageningen, The Netherlands
| | - René H. Wijffels
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, Wageningen, The Netherlands
- Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Packo P. Lamers
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, Wageningen, The Netherlands
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30
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Benvenuti G, Ruiz J, Lamers PP, Bosma R, Wijffels RH, Barbosa MJ. Towards microalgal triglycerides in the commodity markets. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:188. [PMID: 28725268 PMCID: PMC5514516 DOI: 10.1186/s13068-017-0873-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 07/11/2017] [Indexed: 05/04/2023]
Abstract
BACKGROUND Microalgal triglycerides (TAGs) hold great promise as sustainable feedstock for commodity industries. However, to determine research priorities and support business decisions, solid techno-economic studies are essential. Here, we present a techno-economic analysis of two-step TAG production (growth reactors are operated in continuous mode such that multiple batch-operated stress reactors are inoculated and harvested sequentially) for a 100-ha plant in southern Spain using vertically stacked tubular photobioreactors. The base case is established with outdoor pilot-scale data and based on current process technology. RESULTS For the base case, production costs of 6.7 € per kg of biomass containing 24% TAG (w/w) were found. Several scenarios with reduced production costs were then presented based on the latest biological and technological advances. For instance, much effort should focus on increasing the photosynthetic efficiency during the stress and growth phases, as this is the most influential parameter on production costs (30 and 14% cost reduction from base case). Next, biological and technological solutions should be implemented for a reduction in cooling requirements (10 and 4.5% cost reduction from base case when active cooling is avoided and cooling setpoint is increased, respectively). When implementing all the suggested improvements, production costs can be decreased to 3.3 € per kg of biomass containing 60% TAG (w/w) within the next 8 years. CONCLUSIONS With our techno-economic analysis, we indicated a roadmap for a substantial cost reduction. However, microalgal TAGs are not yet cost efficient when compared to their present market value. Cost-competiveness strictly relies on the valorization of the whole biomass components and on cheaper PBR designs (e.g. plastic film flat panels). In particular, further research should focus on the development and commercialization of PBRs where active cooling is avoided and stable operating temperatures are maintained by the water basin in which the reactor is placed.
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Affiliation(s)
- Giulia Benvenuti
- Bioprocess Engineering, AlgaePARC, Wageningen University, P.O. Box 16, 6700 AA Wageningen, The Netherlands
| | - Jesús Ruiz
- Algades–Alga, Development, Engineering and Services, S.L., c. Margaritas, Costa Oeste, El Puerto de Santa María, 11500 Cádiz, Spain
| | - Packo P. Lamers
- Bioprocess Engineering, AlgaePARC, Wageningen University, P.O. Box 16, 6700 AA Wageningen, The Netherlands
| | - Rouke Bosma
- Bioprocess Engineering, AlgaePARC, Wageningen University, P.O. Box 16, 6700 AA Wageningen, The Netherlands
| | - René H. Wijffels
- Bioprocess Engineering, AlgaePARC, Wageningen University, P.O. Box 16, 6700 AA Wageningen, The Netherlands
- Biosciences and Aquaculture, Nord University, 8049 Bodø, Norway
| | - Maria J. Barbosa
- Bioprocess Engineering, AlgaePARC, Wageningen University, P.O. Box 16, 6700 AA Wageningen, The Netherlands
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