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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: 10] [Impact Index Per Article: 3.3] [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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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: 1.8] [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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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: 19] [Impact Index Per Article: 4.8] [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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Tseng M, Di Filippo CM, Fung M, Kim JO, Forster IP, Zhou Y. Cascading effects of algal warming in a freshwater community. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michelle Tseng
- Departments of Botany and Zoology University of British Columbia Vancouver BC Canada
| | | | - Madeline Fung
- Departments of Botany and Zoology University of British Columbia Vancouver BC Canada
| | - Jihyun O. Kim
- Departments of Botany and Zoology University of British Columbia Vancouver BC Canada
| | | | - Yilin Zhou
- Departments of Botany and Zoology University of British Columbia Vancouver BC Canada
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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: 11] [Impact Index Per Article: 2.8] [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: 20] [Impact Index Per Article: 4.0] [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: 3.8] [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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Nie J, Sun Y, Zhou Y, Kumar M, Usman M, Li J, Shao J, Wang L, Tsang DCW. Bioremediation of water containing pesticides by microalgae: Mechanisms, methods, and prospects for future research. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 707:136080. [PMID: 31869621 DOI: 10.1016/j.scitotenv.2019.136080] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 11/20/2019] [Accepted: 12/10/2019] [Indexed: 05/27/2023]
Abstract
The application of pesticides reduces the loss of crops while simultaneously increasing crop productivity. However, the frequent use of pesticides can cause serious environmental problems due to their high accumulative and persistent nature. Recently, microalgae technology has received considerable success in the efficient treatment of pesticides pollution. In this review, the metabolic mechanisms responsible for the removal of pesticides are summarized based on previous studies. Different methods used to enhance the ability of microalgae to remove pesticides are critically evaluated. The recycling of microalgae biomass after wastewater treatment for biochar preparation and biodiesel production using the biorefinery approach is also introduced. Furthermore, we present potential future research directions to highlight the prospects of microalgae research in the removal of pesticides along with the production of value-added products.
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Affiliation(s)
- Jing Nie
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China
| | - Yuqing Sun
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Yaoyu Zhou
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China.
| | - Manish Kumar
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Muhammad Usman
- PEIE Research Chair for the Development of Industrial Estates and Free Zones, Center for Environmental Studies and Research, Sultan Qaboos University, Al-Khoud 123, Oman
| | - Jiangshan Li
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Jihai Shao
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China
| | - Lei Wang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
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Di Caprio F, Pagnanelli F, Wijffels RH, Van der Veen D. Quantification of Tetradesmus obliquus (Chlorophyceae) cell size and lipid content heterogeneity at single-cell level. JOURNAL OF PHYCOLOGY 2018; 54:187-197. [PMID: 29194643 DOI: 10.1111/jpy.12610] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 11/08/2017] [Indexed: 06/07/2023]
Abstract
Much of our current knowledge of microbial growth is obtained from studies at a population level. Driven by the realization that processes that operate within a population might influence a population's behavior, we sought to better understand Tetradesmus obliquus (formerly Scenedesmus obliquus) physiology at the cellular level. In this work, an accurate pretreatment method to quantitatively obtain single cells of T. obliquus, a coenobia-forming alga, is described. These single cells were examined by flow cytometry for triacylglycerol (TAG), chlorophyll, and protein content, and their cell sizes were recorded by coulter counter. We quantified heterogeneity of size and TAG content at single-cell level for a population of T. obliquus during a controlled standard batch cultivation. Unexpectedly, variability of TAG content per cell within the population increased throughout the batch run, up to 400 times in the final stage of the batch run, with values ranging from 0.25 to 99 pg · cell-1 . Two subpopulations, classified as having low or high TAG content per cell, were identified. Cell size also increased during batch growth with average values from 36 to 70 μm3 · cell-1 ; yet cell size variability increased only up to 16 times. Cell size and cellular TAG content were not correlated at the single-cell level. Our data show clearly that TAG production is affected by cell-to-cell variation, which suggests that its control and better understanding of the underlying processes may improve the productivity of T. obliquus for industrial processes such as biodiesel production.
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Affiliation(s)
- Fabrizio Di Caprio
- Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Francesca Pagnanelli
- Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Rene H Wijffels
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
- Faculty of Bioscuences and Aquaculture, Nord University, N-8049, Bodø, Norway
| | - Douwe Van der Veen
- Bioprocess Engineering & AlgaePARC, Wageningen University and Research, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
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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: 6.0] [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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Imaging the accumulated intracellular microalgal lipids as a response to temperature stress. 3 Biotech 2017; 7:41. [PMID: 28439814 DOI: 10.1007/s13205-017-0677-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 02/27/2017] [Indexed: 01/13/2023] Open
Abstract
Over the last few decades, many scientists considered microalgae as promising actors for future biofuels because of the high lipid productivity inside their cells. Moreover, much attention has been paid to algal lipids as they can be used in biodiesel production. In this study, we optimized the different suitable conditions such as incubation time, incubation temperature, Dimethylesulfoxide and Nile red concentrations of the lipophilic fluorescence dye Nile red as an excellent and fast vital stain to detect and quantify intracellular lipids. This was achieved using the green alga Nannochloropsis salina. In addition, investigating the accumulation of lipid vesicles inside different isolated microalgal species as a response to temperature stress. Furthermore, the confocal laser scanning microscopy (LS510) for imaging and measuring the size and volume of the accumulated lipid vesicles was used.
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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: 1.4] [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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13
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Dashkova V, Malashenkov D, Poulton N, Vorobjev I, Barteneva NS. Imaging flow cytometry for phytoplankton analysis. Methods 2017; 112:188-200. [DOI: 10.1016/j.ymeth.2016.05.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 05/13/2016] [Indexed: 10/21/2022] Open
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Klassen V, Blifernez-Klassen O, Wobbe L, Schlüter A, Kruse O, Mussgnug JH. Efficiency and biotechnological aspects of biogas production from microalgal substrates. J Biotechnol 2016; 234:7-26. [DOI: 10.1016/j.jbiotec.2016.07.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 07/13/2016] [Accepted: 07/18/2016] [Indexed: 11/17/2022]
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15
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Back A, Rossignol T, Krier F, Nicaud JM, Dhulster P. High-throughput fermentation screening for the yeast Yarrowia lipolytica with real-time monitoring of biomass and lipid production. Microb Cell Fact 2016; 15:147. [PMID: 27553851 PMCID: PMC4995649 DOI: 10.1186/s12934-016-0546-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 08/15/2016] [Indexed: 11/22/2022] Open
Abstract
Background Because the model yeast Yarrowia lipolytica can synthesize and store lipids in quantities up to 20 % of its dry weight, it is a promising microorganism for oil production at an industrial scale. Typically, optimization of the lipid production process is performed in the laboratory and later scaled up for industrial production. However, the scale-up process can be complicated by genetic modifications that are optimized for one set of growing conditions can confer a less-than-optimal phenotype in a different environment. To address this issue, small cultivation systems have been developed that mimic the conditions in benchtop bioreactors. In this work, we used one such microbioreactor system, the BioLector, to develop high-throughput fermentation procedures that optimize growth and lipid accumulation in Y. lipolytica. Using this system, we were able to monitor lipid and biomass production in real time throughout the culture duration. Results The BioLector can monitor the growth of Y. lipolytica in real time by evaluating scattered light; this produced accurate measurements until cultures reached an equivalent of OD600nm = 115 and a cell dry weight of 100 g L−1. In addition, a lipid-specific fluorescent probe was applied which reliably monitored lipid production up to a concentration of 12 g L−1. Through screening various growing conditions, we determined that a carbon/nitrogen ratio of 35 was the most efficient for lipid production. Further screening showed that ammonium chloride and glycerol were the most valuable nitrogen and carbon sources, respectively, for growth and lipid production. Moreover, a carbon concentration above 1 M appeared to impair growth and lipid accumulation. Finally, we used these optimized conditions to screen engineered strains of Y. lipolytica with high lipid-accumulation capability. The growth and lipid content of the strains cultivated in the BioLector were compared to those grown in benchtop bioreactors. Conclusion To our knowledge, this is the first time that the BioLector has been used to track lipid production in real time and to monitor the growth of Y. lipolytica. The present study also showed the efficacy of the BioLector in screening growing conditions and engineered strains prior to scale-up. The method described here could be applied to other oleaginous microorganisms.
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Affiliation(s)
- Alexandre Back
- Univ. Lille, INRA, ISA, Univ. Artois, Univ. Littoral Côte d'Opale, EA 7394-ICV- Institut Charles Viollette, F-59000, Lille, France.,Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-En-Josas, France
| | - Tristan Rossignol
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-En-Josas, France
| | - François Krier
- Univ. Lille, INRA, ISA, Univ. Artois, Univ. Littoral Côte d'Opale, EA 7394-ICV- Institut Charles Viollette, F-59000, Lille, France.
| | - Jean-Marc Nicaud
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-En-Josas, France
| | - Pascal Dhulster
- Univ. Lille, INRA, ISA, Univ. Artois, Univ. Littoral Côte d'Opale, EA 7394-ICV- Institut Charles Viollette, F-59000, Lille, France
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16
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Challagulla V, Nayar S, Walsh K, Fabbro L. Advances in techniques for assessment of microalgal lipids. Crit Rev Biotechnol 2016; 37:566-578. [PMID: 27417693 DOI: 10.1080/07388551.2016.1206058] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Microalgae are a varied group of organisms with considerable commercial potential as sources of various biochemicals, storage molecules and metabolites such as lipids, sugars, amino acids, pigments and toxins. Algal lipids can be processed to bio-oils and biodiesel. The conventional method to estimate algal lipids is based on extraction using solvents and quantification by gravimetry or chromatography. Such methods are time consuming, use hazardous chemicals and are labor intensive. For rapid screening of prospective algae or for management decisions (e.g. decision on timing of harvest), a rapid, high throughput, reliable, accurate, cost effective and preferably nondestructive analytical technique is desirable. This manuscript reviews the application of fluorescent lipid soluble dyes (Nile Red and BODIPY 505/515), nuclear magnetic resonance (NMR), Raman, Fourier transform infrared (FTIR) and near infrared (NIR) spectroscopy for the assessment of lipids in microalgae.
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Affiliation(s)
- Vineela Challagulla
- a School of Medical and Applied Sciences , Central Queensland University , Rockhampton , QLD , Australia
| | - Sasi Nayar
- b South Australian Research and Development Institute - Aquatic Sciences , West Beach , South Australia , Australia
| | - Kerry Walsh
- a School of Medical and Applied Sciences , Central Queensland University , Rockhampton , QLD , Australia
| | - Larelle Fabbro
- a School of Medical and Applied Sciences , Central Queensland University , Rockhampton , QLD , Australia
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Hounslow E, Noirel J, Gilmour DJ, Wright PC. Lipid quantification techniques for screening oleaginous species of microalgae for biofuel production. EUR J LIPID SCI TECH 2016. [DOI: 10.1002/ejlt.201500469] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Emily Hounslow
- Department of Chemical and Biological Engineering; ChELSI Institute; The University of Sheffield; Sheffield UK
- Department of Molecular Biology and Biotechnology; The University of Sheffield; Sheffield UK
| | - Josselin Noirel
- Chaire de Bioinformatique; LGBA; Conservatoire National des Arts et Métiers; Paris France
| | - D. James Gilmour
- Department of Molecular Biology and Biotechnology; The University of Sheffield; Sheffield UK
| | - Phillip C. Wright
- Department of Chemical and Biological Engineering; ChELSI Institute; The University of Sheffield; Sheffield UK
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Cabanelas ITD, van der Zwart M, Kleinegris DMM, Wijffels RH, Barbosa MJ. Sorting cells of the microalga Chlorococcum littorale with increased triacylglycerol productivity. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:183. [PMID: 27582875 PMCID: PMC5006580 DOI: 10.1186/s13068-016-0595-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/19/2016] [Indexed: 05/21/2023]
Abstract
BACKGROUND Despite extensive research in the last decades, microalgae are still only economically feasible for high valued markets. Strain improvement is a strategy to increase productivities, hence reducing costs. In this work, we focus on microalgae selection: taking advantage of the natural biological variability of species to select variations based on desired characteristics. We focused on triacylglycerol (TAG), which have applications ranging from biodiesel to high-value omega-3 fatty-acids. Hence, we demonstrated a strategy to sort microalgae cells with increased TAG productivity. RESULTS 1. We successfully identified sub-populations of cells with increased TAG productivity using Fluorescence assisted cell sorting (FACS). 2. We sequentially sorted cells after repeated cycles of N-starvation, resulting in five sorted populations (S1-S5). 3. The comparison between sorted and original populations showed that S5 had the highest TAG productivity [0.34 against 0.18 g l(-1) day(-1) (original), continuous light]. 4. Original and S5 were compared in lab-scale reactors under simulated summer conditions confirming the increased TAG productivity of S5 (0.4 against 0.2 g l(-1) day(-1)). Biomass composition analyses showed that S5 produced more biomass under N-starvation because of an increase only in TAG content and, flow cytometry showed that our selection removed cells with lower efficiency in producing TAGs. CONCLUSIONS All combined, our results present a successful strategy to improve the TAG productivity of Chlorococcum littorale, without resourcing to genetic manipulation or random mutagenesis. Additionally, the improved TAG productivity of S5 was confirmed under simulated summer conditions, highlighting the industrial potential of S5 for microalgal TAG production.
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Affiliation(s)
| | | | | | - René H. Wijffels
- Wageningen UR, Bioprocess Engineering, Wageningen, The Netherlands
- Faculty Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Maria J. Barbosa
- Wageningen UR, Bioprocess Engineering, Wageningen, The Netherlands
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19
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Optimization of a Nile Red method for rapid lipid determination in autotrophic, marine microalgae is species dependent. J Microbiol Methods 2015; 118:152-8. [PMID: 26388510 DOI: 10.1016/j.mimet.2015.09.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 09/17/2015] [Accepted: 09/17/2015] [Indexed: 11/20/2022]
Abstract
Several studies have been conducted to develop rapid methods for quantification of lipid content in microalgae, as an alternative for time consuming gravimetric methods. Different studies showed that lipid staining with Nile Red in whole cell suspensions and subsequently quantification by the use of a spectrofluorometric device is a promising method, but a profound optimization and validation is rare. It has already been proven that the correlation curve for quantification is species dependent, but it has not yet been investigated whether this is also the case for the optimization of the Nile Red assay protocol. Therefore, two autotrophic, marine microalgae, Nannochloropsis oculata and T-Isochrysis lutea, strongly differing in e.g. cell wall structure, were selected in this study to investigate whether optimization of the Nile Red assay is species dependent. Besides this, it was checked for one of these species, Nannochloropsis, whether the lipid content, determined by the Nile Red assay, could indeed be correlated with the neutral and/or total lipid content determined by gravimetric methods. It was found that optimization of the Nile Red assay was strongly species dependent. Consequently, optimization has to be done for each species before using the assay. For Nannochloropsis, a good correlation was found between total and neutral lipid content obtained by the Nile Red assay and by gravimetric methods.
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