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Wang Y, Wang J, Yang S, Liang Q, Gu Z, Wang Y, Mou H, Sun H. Selecting a preculture strategy for improving biomass and astaxanthin productivity of Chromochloris zofingiensis. Appl Microbiol Biotechnol 2024; 108:117. [PMID: 38204137 PMCID: PMC10781847 DOI: 10.1007/s00253-023-12873-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 10/05/2023] [Accepted: 10/17/2023] [Indexed: 01/12/2024]
Abstract
Chromochloris zofingiensis is a potential source of natural astaxanthin; however, its rapid growth and astaxanthin enrichment cannot be achieved simultaneously. This study established autotrophic, mixotrophic, and heterotrophic preculture patterns to assess their ameliorative effect on the C. zofingiensis heterotrophic growth state. In comparison, mixotrophic preculture (MP) exhibited the best improving effect on heterotrophic biomass concentration of C. zofingiensis (up to 121.5 g L-1) in a 20 L fermenter, reaching the global leading level. The astaxanthin productivity achieved 111 mg L-1 day-1, 7.4-fold higher than the best record. The transcriptome and 13C tracer-based metabolic flux analysis were used for mechanism inquiry. The results revealed that MP promoted carotenoid and lipid synthesis, and supported synthesis preference of low unsaturated fatty acids represented by C18:1 and C16:0. The MP group maintained the best astaxanthin productivity via mastering the balance between increasing glucose metabolism and inhibition of carotenoid synthesis. The MP strategy optimized the physiological state of C. zofingiensis and realized its heterotrophic high-density growth for an excellent astaxanthin yield on a pilot scale. This strategy exhibits great application potential in the microalgae-related industry. KEY POINTS: • Preculture strategies changed carbon flux and gene expression in C. zofingiensis • C. zofingiensis realized a high-density culture with MP and fed-batch culture (FBC) • Astaxanthin productivity achieved 0.111 g L-1 day-1 with MP and FBC.
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Affiliation(s)
- Yuxin Wang
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China
| | - Jia Wang
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China
| | - Shufang Yang
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Qingping Liang
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China
| | - Ziqiang Gu
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China
| | - Ying Wang
- Marine Science research Institute of Shandong Province, Qingdao, 266003, China.
| | - Haijin Mou
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China.
| | - Han Sun
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China.
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2
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Şirin PA, Serdar S. Effects of nitrogen starvation on growth and biochemical composition of some microalgae species. Folia Microbiol (Praha) 2024:10.1007/s12223-024-01136-5. [PMID: 38285280 DOI: 10.1007/s12223-024-01136-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 01/12/2024] [Indexed: 01/30/2024]
Abstract
Nitrogen is one of the most important nutrient sources for the growth of microalgae. We studied the effects of nitrogen starvation on the growth responses, biochemical composition, and fatty acid profile of Dunaliella tertiolecta, Phaeodactylum tricornutum, and Nannochloropsis oculata. The lack of nitrogen caused changes in carbohydrate, protein, lipid, and fatty acid composition in all examined microalgae. The carbohydrate content increased 59% in D. tertiolecta, while the lipid level increased 139% in P. tricornutum under nitrogen stress conditions compared to the control groups. Nitrogen starvation increased the oligosaccharide and polysaccharide contents of D. tertiolecta 4.1-fold and 3.6-fold, respectively. Furthermore, triacylglycerol (TAG) levels in N. oculata and P. tricornutum increased 2.3-fold and 7.4-fold, respectively. The dramatic increase in the amount of TAG is important for the use of these microalgae as raw materials in biodiesel. Nitrogen starvation increased the amounts of oligosaccharides and polysaccharides of D. tertiolecta, while increased eicosapentaenoic acid (EPA) in N. oculata and docosahexaenoic acid (DHA) content in P. tricornutum. The amount of polyunsaturated fatty acids (PUFAs), EPA, DHA, oligosaccharides, and polysaccharides in microalgal species can be increased without using the too costly nitrogen source in the culture conditions, which can reduce the most costly of living feeding.
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Affiliation(s)
- Pınar Akdoğan Şirin
- Fatsa Faculty of Marine Science, Department of Fisheries Technology Engineering, Ordu University, 52400, Fatsa, Ordu, Turkey.
| | - Serpil Serdar
- Faculty of Fisheries, Department of Aquaculture, Ege University, 35030, Bornova, Izmir, Turkey
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3
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Wang Y, Wang J, Gu Z, Yang S, He Y, Mou H, Sun H. Altering autotrophic carbon metabolism of Nitzschia closterium to mixotrophic mode for high-value product improvement. BIORESOURCE TECHNOLOGY 2023; 371:128596. [PMID: 36638896 DOI: 10.1016/j.biortech.2023.128596] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 01/02/2023] [Accepted: 01/07/2023] [Indexed: 06/17/2023]
Abstract
An adaptive laboratory evolution (ALE) strategy was designed to evolve autotrophic Nitzschia closterium to mixotrophic growth for high productivity of essential amino acid (EAA), eicosapentaenoic acid (EPA) and fucoxanthin. The N. closterium growth was limited under glucose initially, but a red light emitting diode was innovatively applied to modify carbon metabolism and obtain mixotrophic strain of N. closterium GM. The N. closterium GM biomass concentration was improved by 65.07% comparing with wild type, but exhibited weak photosynthesis and strong glucose metabolism. At carbon metabolism levels, ALE promoted NADPH oxidase activity and induced protein degradation to lipid biosynthesis by elevating acetyl-CoA and pyruvate contents. It also improved carbon flux to TCA cycle, and elevated contents of glucose-6-phosphate, fructose-6-phosphate, glyceraldehyde-3-phosphate for providing sufficient ATP and NADPH. Productivities of EPA, EAA and fucoxanthin were increased by 41.0%, 18.8% and 20.4%, respectively. This ALE strategy was promising in microalgal production of high-value products.
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Affiliation(s)
- Yuxin Wang
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Jia Wang
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Ziqiang Gu
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Shufang Yang
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Institute for Innovative Development of Food Industry, Shenzhen University, Shenzhen 518060, China
| | - Yongjin He
- College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Haijin Mou
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Han Sun
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Institute for Innovative Development of Food Industry, Shenzhen University, Shenzhen 518060, China.
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4
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Liufu W, Di M, Yingying P, Liqiu S, Wenzhi W. Nitrogen limitation and hydrogen peroxide act synergistically to enhance lipids accumulation via ROS/Ca2+ dependent mechanism in Chlorella sorokiniana. ALGAL RES 2023. [DOI: 10.1016/j.algal.2023.102974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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5
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Oyama T, Kato Y, Hidese R, Matsuda M, Matsutani M, Watanabe S, Kondo A, Hasunuma T. Development of a stable semi-continuous lipid production system of an oleaginous Chlamydomonas sp. mutant using multi-omics profiling. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:95. [PMID: 36114515 PMCID: PMC9482161 DOI: 10.1186/s13068-022-02196-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 09/01/2022] [Indexed: 11/30/2022]
Abstract
Background Microalgal lipid production has attracted global attention in next-generation biofuel research. Nitrogen starvation, which drastically suppresses cell growth, is a common and strong trigger for lipid accumulation in microalgae. We previously developed a mutant Chlamydomonas sp. KAC1801, which can accumulate lipids irrespective of the presence or absence of nitrates. This study aimed to develop a feasible strategy for stable and continuous lipid production through semi-continuous culture of KAC1801. Results KAC1801 continuously accumulated > 20% lipid throughout the subculture (five generations) when inoculated with a dry cell weight of 0.8–0.9 g L−1 and cultured in a medium containing 18.7 mM nitrate, whereas the parent strain KOR1 accumulated only 9% lipid. Under these conditions, KAC1801 continuously produced biomass and consumed nitrates. Lipid productivity of 116.9 mg L−1 day−1 was achieved by semi-continuous cultivation of KAC1801, which was 2.3-fold higher than that of KOR1 (50.5 mg L−1 day−1). Metabolome and transcriptome analyses revealed a depression in photosynthesis and activation of nitrogen assimilation in KAC1801, which are the typical phenotypes of microalgae under nitrogen starvation. Conclusions By optimizing nitrate supply and cell density, a one-step cultivation system for Chlamydomonas sp. KAC1801 under nitrate-replete conditions was successfully developed. KAC1801 achieved a lipid productivity comparable to previously reported levels under nitrogen-limiting conditions. In the culture system of this study, metabolome and transcriptome analyses revealed a nitrogen starvation-like response in KAC1801. Supplementary Information The online version contains supplementary material available at 10.1186/s13068-022-02196-w.
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Sousa S, Freitas AC, Gomes AM, Carvalho AP. Modulated stress to balance Nannochloropsis oculata growth and eicosapentaenoic acid production. Appl Microbiol Biotechnol 2022; 106:4017-4027. [PMID: 35599259 DOI: 10.1007/s00253-022-11968-1] [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: 02/10/2022] [Revised: 05/05/2022] [Accepted: 05/07/2022] [Indexed: 11/30/2022]
Abstract
Two environmental parameters, temperature and light intensity, were independently used as stress modulators to enhance eicosapentaenoic acid (EPA) production by the microalga Nannochloropsis oculata, without hindering biomass production. A sinusoidal approach was used, as environmental conditions were alternated between optimum and stress status in multi-day cycles. Low temperatures (5 and 10 °C) and light intensities (30 and 50 μmol photons/m2/s) were tested. Results revealed that the modulated stress approach used was able to avoid decreases in biomass production. Temperature stress (10 °C) presented the highest impact, increasing EPA content to 12.8 mgEPA/L, 158% more than the amount obtained in optimum (non-modulated) growth conditions at that point in time, while the lower light intensity stress was able to increase to 126% more. It is important to point out that in both cases increases in EPA amounts resulted from increased content in each individual cell and not just from increased biomass contents. KEY POINTS: • Temperature stress (10 °C) presented the highest impact increasing EPA content 158% • Lower light intensity stress was able to increase EPA to 126% more • EPA increased in individual cell contents simultaneous with biomass increase.
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Affiliation(s)
- Sérgio Sousa
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia E Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005, Porto, Portugal.,REQUIMTE/LAQV, Instituto Superior de Engenharia, Instituto Politécnico Do Porto, Rua Dr. António Bernardino de Almeida, 431, 4200-072, Porto, Portugal
| | - Ana C Freitas
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia E Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005, Porto, Portugal
| | - Ana M Gomes
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia E Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005, Porto, Portugal.
| | - Ana P Carvalho
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia E Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005, Porto, Portugal.,REQUIMTE/LAQV, Instituto Superior de Engenharia, Instituto Politécnico Do Porto, Rua Dr. António Bernardino de Almeida, 431, 4200-072, Porto, Portugal
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Seawater with Added Monosodium Glutamate Residue (MSGR) Is a Promising Medium for the Cultivation of Two Commercial Marine Microalgae. WATER 2022. [DOI: 10.3390/w14060975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Phaeodactylum tricornutum and Nannochloropsis oceanica, with their satisfactory performance in accumulating lipids and other high-value products, have been successfully used for commercial production in recent years. However, costly chemicals in culture media greatly increase the price of the resulting bioproducts. To control the cultivation cost, this paper assessed the potential of seawater supplemented with monosodium glutamate residue wastewater at a ratio of 1/500 (S-MSGR) to serve as a growing medium for these two marine species. Compared with the standard chemical culture medium, Erdschreiber’s medium (EM), both the algal growth and metabolite accumulation of P. tricornutum and N. oceanica were greatly promoted in S-MSGR. The maximum biomass concentrations of P. tricornutum and N. oceanica reached 0.93 and 0.36 g/L, which were, respectively, 1.5 and 1.9 times higher than those in EM medium. For lipid accumulation, P. tricornutum exhibited an excellent lipid productivity of 22.9 mg/L/day in S-MSGR, a 64% increase compared to EM medium. Furthermore, the average yield coefficients indicated good performance of P. tricornutum and N. oceanica in transferring the nitrogen in S-MSGR to the biomass, at 74.8 and 174.8 mg/g of nitrogen. In addition, compared with EM, the costs of the medium for lipid production of P. tricornutum and N. oceanica cultured in S-MSGR were USD 2.3 and 5.8/(kg lipid), which saved 96.9% and 97.6%, respectively. Therefore, this paper demonstrates that S-MSGR is a suitable nutrient resource for P. tricornutum and N. oceanica, and it has a great potential to cut the cultivation cost during real commercial production.
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8
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Liu T, Chen Z, Xiao Y, Yuan M, Zhou C, Liu G, Fang J, Yang B. Biochemical and Morphological Changes Triggered by Nitrogen Stress in the Oleaginous Microalga Chlorella vulgaris. Microorganisms 2022; 10:microorganisms10030566. [PMID: 35336142 PMCID: PMC8949318 DOI: 10.3390/microorganisms10030566] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/20/2022] [Accepted: 02/25/2022] [Indexed: 02/06/2023] Open
Abstract
Oleaginous microalgae have been considered promising sources of biodiesel due to their high lipid content. Nitrogen limitation/starvation is one of the most prominent strategies to induce lipid accumulation in microalgae. Nonetheless, despite numerous studies, the mechanism underlying this approach is not well understood. The aim of this study was to investigate the effect of nitrogen limitation and starvation on biochemical and morphological changes in the microalga Chlorella vulgaris FACHB-1068, thereby obtaining the optimal nitrogen stress strategy for maximizing the lipid productivity of microalgal biomass. The results showed that nitrogen limitation (nitrate concentration < 21.66 mg/L) and starvation enhanced the lipid content but generally decreased the biomass productivity, pigment concentration, and protein content in algal cells. Comparatively, 3-day nitrogen starvation was found to be a more suitable strategy to produce lipid-rich biomass. It resulted in an increased biomass production and satisfactory lipid content of 266 mg/L and 31.33%, respectively. Besides, nitrogen starvation caused significant changes in cell morphology, with an increase in numbers and total size of lipid droplets and starch granules. Under nitrogen starvation, saturated fatty acids (C-16:0, C-20:0, and C-18:0) accounted for the majority of the total fatty acids (~80%), making C. vulgaris FACHB-1068 a potential feedstock for biodiesel production. Our work may contribute to a better understanding of the biochemical and morphological changes in microalgae under nitrogen stress. Besides, our work may provide valuable information on increasing the lipid productivity of oleaginous microalgae by regulating nitrogen supply.
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Affiliation(s)
| | | | | | | | | | | | | | - Bo Yang
- Correspondence: (J.F.); (B.Y.)
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Manipulation of triacylglycerol biosynthesis in Nannochloropsis oceanica by overexpressing an Arabidopsis thaliana diacylglycerol acyltransferase gene. ALGAL RES 2022. [DOI: 10.1016/j.algal.2021.102590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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10
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Improving astaxanthin production of Haematococcus pluvialis by an efficient fed-batch strategy in a photobioreactor. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102539] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Premaratne M, Liyanaarachchi VC, Nimarshana P, Ariyadasa TU, Malik A, Attalage RA. Co-production of fucoxanthin, docosahexaenoic acid (DHA) and bioethanol from the marine microalga Tisochrysis lutea. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108160] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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12
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Coordinating Carbon Metabolism and Cell Cycle of Chlamydomonasreinhardtii with Light Strategies under Nitrogen Recovery. Microorganisms 2021; 9:microorganisms9122480. [PMID: 34946081 PMCID: PMC8707240 DOI: 10.3390/microorganisms9122480] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 11/26/2021] [Accepted: 11/29/2021] [Indexed: 11/17/2022] Open
Abstract
Nutrient supplementation is common in microalgae cultivation to enhance the accumulation of biomass and biofunctional products, while the recovery mechanism from nutrient starvation is less investigated. In this study, the influence of remodeled carbon metabolism on cell cycle progression was explored by using different light wavelengths under N-repletion and N-recovery. The results suggested that blue light enhanced cell enlargement and red light promoted cell division under N-repletion. On the contrary, blue light promoted cell division by stimulating cell cycle progression under N-recovery. This interesting phenomenon was ascribed to different carbon metabolisms under N-repletion and N-recovery. Blue light promoted the recovery of photosystem II and redirected carbon skeletons into proteins under N-recovery, which potentially accelerated cell recovery and cell cycle progression. Although red light also facilitated the recovery of photosystem II, it mitigated the degradation of polysaccharide and then arrested almost all the cells in the G1 phase. By converting light wavelengths at the 12 h of N-recovery with blue light, red and white lights were proved to increase biomass concentration better than continuous blue light. These results revealed different mechanisms of cell metabolism of Chlamydomonas reinhardtii during N-recovery and could be applied to enhance cell vitality of microalgae from nutrient starvation and boost biomass production.
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Sun H, Ren Y, Fan Y, Lu X, Zhao W, Chen F. Systematic metabolic tools reveal underlying mechanism of product biosynthesis in Chromochloris zofingiensis. BIORESOURCE TECHNOLOGY 2021; 337:125406. [PMID: 34147773 DOI: 10.1016/j.biortech.2021.125406] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/08/2021] [Accepted: 06/09/2021] [Indexed: 06/12/2023]
Abstract
This study comprehensively explored underlying mechanism of fed-batch culture on product biosynthesis in Chromochloris zofingiensis by dynamic model, targeted metabolite determination, enzyme activity analysis, and 13C tracer-based metabolic flux analysis. Based on dynamic models of cell growth and product formation, exponential fed-batch culture and fed-batch culture based on pH changes were established to increase biomass concentration by 20.05-fold and 18.28-fold, respectively. Exponential fed-batch culture exhibited great potentials in biodiesel and protein productions from microalgae. Systematic metabolic tools revealed fed-batch culture limited photosynthetic efficiency by inhibiting photosystem and Rubisco activity, while strengthened respiratory action to provide more substances and energy for product biosynthesis. Fed-batch culture elevated biosynthetic capability for carotenoid and lipid by promoting related metabolic flux and contents of pyruvate and ace-CoA. Finally, economic analysis revealed biomass cost was decreased to 1.99 $/kg from 2.39 $/kg, suggesting fed-batch culture was a cost-effective strategy to improve economic viability of microalgal production.
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Affiliation(s)
- Han Sun
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China; Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871, China
| | - Yuanyuan Ren
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Shenzhen University, Shenzhen 518060, China; Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871, China
| | - Yuwei Fan
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Xue Lu
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871, China
| | - Weiyang Zhao
- Department of Food Science, Cornell University, Ithaca, NY 14853, USA
| | - Feng Chen
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Shenzhen University, Shenzhen 518060, China.
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Zhang L, Ye SC, Chen WB, Han JC, Tian JJ, Zhang YB, Xu JL, Cao JY, Qin C. Screening the rate-limiting genes in the ω6 polyunsaturated fatty acid biosynthesis pathway in Nannochloropsis oceanica. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102342] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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15
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Heredia V, Pruvost J, Gonçalves O, Drouin D, Marchal L. Lipid recovery from Nannochloropsis gaditana using the wet pathway: Investigation of the operating parameters of bead milling and centrifugal extraction. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102318] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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16
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Li Q, Zhao Y, Ding W, Han B, Geng S, Ning D, Ma T, Yu X. Gamma-aminobutyric acid facilitates the simultaneous production of biomass, astaxanthin and lipids in Haematococcus pluvialis under salinity and high-light stress conditions. BIORESOURCE TECHNOLOGY 2021; 320:124418. [PMID: 33221643 DOI: 10.1016/j.biortech.2020.124418] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 11/11/2020] [Accepted: 11/11/2020] [Indexed: 05/20/2023]
Abstract
The effects of γ-aminobutyric acid (GABA) on the biomass and astaxanthin and lipids production in Haematococcus pluvialis under combined salinity stress and high-light stresses were investigated. The results showed that the highest biomass (1.65 g L-1), astaxanthin production (3.86 mg L-1 d-1) and lipids content (55.11%) in H. pluvialis LUGU were observed under the 0.25 mM GABA treatment. Moreover, compared with salinity and high-light stress, GABA treatment also increased the transcript levels of biosynthesis genes, the contents of endogenous GABA and carbohydrates but decreased reactive oxygen species (ROS) levels. Further evidence revealed that intracellular GABA could regulate cell growth, astaxanthin production and lipids synthesis by mediating carotenogenesis, lipogenesis and ROS signalling. Collectively, this study provides a combined strategy for promoting the coproduction of astaxanthin and lipids and sheds light on the regulatory mechanism through which GABA affects cell growth, astaxanthin production and lipids biosynthesis in H. pluvialis under unfavourable conditions.
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Affiliation(s)
- Qingqing Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Yongteng Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Wei Ding
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Benyong Han
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Shuxiang Geng
- Yunnan Academy of Forestry and Grassland, Kunming 650051, China
| | - Delu Ning
- Yunnan Academy of Forestry and Grassland, Kunming 650051, China
| | - Ting Ma
- Yunnan Academy of Forestry and Grassland, Kunming 650051, China
| | - Xuya Yu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China.
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Efficient conversion of extracts from low-cost, rejected fruits for high-valued Docosahexaenoic acid production by Aurantiochytrium sp. SW1. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101977] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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18
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You W, Wei L, Gong Y, Hajjami ME, Xu J, Poetsch A. Integration of proteome and transcriptome refines key molecular processes underlying oil production in Nannochloropsis oceanica. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:109. [PMID: 32565907 PMCID: PMC7302151 DOI: 10.1186/s13068-020-01748-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 06/08/2020] [Indexed: 05/03/2023]
Abstract
BACKGROUND Under nitrogen deficiency situation, Nannochloropsis spp. accumulate large amounts of lipids in the form of triacylglycerides (TAG). Mechanisms of this process from the perspective of transcriptome and metabolome have been obtained previously, yet proteome analysis is still sparse which hinders the analysis of dynamic adaption to nitrogen deficiency. Here, proteomes for 3 h, 6 h, 12 h, 24 h, 48 h and 10th day of nitrogen deplete (N-) and replete (N+) conditions were obtained and integrated with previous transcriptome data for N. oceanica. RESULTS Physiological adaptations to N- not apparent from transcriptome data were unveiled: (a) abundance of proteins related to photosynthesis only slightly decreased in the first 48 h, indicating that photosynthesis is still working efficiently, and protein amounts adjust gradually with reduction in chloroplast size. (b) Most proteins related to the TCA cycle were strongly upregulated after 48 h under N-, suggesting that respiration is enhanced after 48 h and that TCA cycle efflux supports the carbon required for lipid synthesis. (c) Proteins related to lipid accumulation via the Kennedy pathway increased their abundance at 48 h, synchronous with the previously reported diversification of fatty acids after 48 h. CONCLUSIONS This study adds a proteome perspective on the major pathways for TAG accumulation in Nannochloropsis spp. Temporal changes of proteome exhibited distinct adaptation phases that are usually delayed relative to transcriptomic responses. Notably, proteome data revealed that photosynthesis and carbon fixation are still ongoing even after 48 h of N-. Moreover, sometimes completely opposite trends in proteome and transcriptome demonstrate the relevance of underexplored post-transcriptional regulation for N- adaptation.
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Affiliation(s)
- Wuxin You
- Single-Cell Center CAS Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong China
- Department of Plant Biochemistry, Ruhr University Bochum, Bochum, Germany
| | - Li Wei
- Single-Cell Center CAS Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong China
- University of Chinese Academy of Science, Beijing, China
| | - Yanhai Gong
- Single-Cell Center CAS Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong China
- University of Chinese Academy of Science, Beijing, China
| | - Mohamed El Hajjami
- Department of Plant Biochemistry, Ruhr University Bochum, Bochum, Germany
| | - Jian Xu
- Single-Cell Center CAS Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong China
- University of Chinese Academy of Science, Beijing, China
| | - Ansgar Poetsch
- Department of Plant Biochemistry, Ruhr University Bochum, Bochum, Germany
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237 China
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003 China
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19
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Transcriptomic and metabolomic adaptation of Nannochloropsis gaditana grown under different light regimes. ALGAL RES 2020. [DOI: 10.1016/j.algal.2019.101735] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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20
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Zhao Y, Xing H, Li X, Geng S, Ning D, Ma T, Yu X. Physiological and Metabolomics Analyses Reveal the Roles of Fulvic Acid in Enhancing the Production of Astaxanthin and Lipids in Haematococcus pluvialis under Abiotic Stress Conditions. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:12599-12609. [PMID: 31644277 DOI: 10.1021/acs.jafc.9b04964] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this study, it was found that fulvic acid (FA) enhanced the contents of astaxanthin and lipids in Haematococcus pluvialis under high light and nitrogen starvation conditions by 2- and 1.2-fold, respectively. Meanwhile, the carbohydrate and chlorophyll contents were decreased by FA induction, whereas the levels of reactive oxygen species (ROS) and glutathione (GSH) as well as the expression of astaxanthin and lipid biosynthetic genes were increased. To further explore the interrelation between FA and the biosynthesis of astaxanthin and lipids, a metabolomics analysis of H. pluvialis by combined FA and abiotic stress exposure was conducted by using LC-MS/MS. The contents of some cytoprotective metabolites and signal molecules, including d-maltose, succinate, malic acid, melatonin (MT), and some amino acids, were increased under FA induction and abiotic stress conditions. These metabolites are intermediates in the TCA cycle and Calvin cycle, providing more precursors for the synthesis of astaxanthin and lipids. Moreover, the signal molecules might contribute to enhancing the abiotic stress tolerance. This study provided new insights into the regulatory mechanism of FA on astaxanthin and lipid accumulation in H. pluvialis.
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Affiliation(s)
- Yongteng Zhao
- Faculty of Life Science and Technology , Kunming University of Science and Technology , Kunming 650500 , China
| | - Hailiang Xing
- Faculty of Life Science and Technology , Kunming University of Science and Technology , Kunming 650500 , China
| | - Xingyu Li
- The First People's Hospital of Yunnan , Kunming 650100 , China
| | | | - Delu Ning
- Yunnan Academy of Forestry , Kunming 650051 , China
| | - Ting Ma
- Yunnan Academy of Forestry , Kunming 650051 , China
| | - Xuya Yu
- Faculty of Life Science and Technology , Kunming University of Science and Technology , Kunming 650500 , China
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21
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Ding W, Li Q, Han B, Zhao Y, Geng S, Ning D, Ma T, Yu X. Comparative physiological and metabolomic analyses of the hyper-accumulation of astaxanthin and lipids in Haematococcus pluvialis upon treatment with butylated hydroxyanisole. BIORESOURCE TECHNOLOGY 2019; 292:122002. [PMID: 31437797 DOI: 10.1016/j.biortech.2019.122002] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 08/09/2019] [Accepted: 08/10/2019] [Indexed: 06/10/2023]
Abstract
The major goal of this study was to explore the functions of butylated hydroxyanisole (BHA) combined with abiotic stress on the cultivation of the microalga Haematococcus pluvialis for astaxanthin and lipid production. Here, the effect of BHA on astaxanthin and lipid accumulation and physiological and metabolomic profiles was investigated. These results suggested that astaxanthin content was increased by 2.17-fold compared to the control. The lipid content was enhanced by 1.22-fold. BHA treatment simultaneously reduced carbohydrates and protein and delayed the decay of chlorophyll. Furthermore, metabolomic analysis demonstrated that BHA upregulated and activated the bioprocesses involved in cellular basal metabolism and signalling systems, such as glycolysis, the TCA cycle, amino acid metabolism and the phosphatidylinositol signalling system, thus enhancing astaxanthin and lipid accumulation. Altogether, this research shows the dramatic effects of BHA on algal metabolism in the regulation of key metabolic nodes and provides novel insights into microalgal regulation and metabolism.
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Affiliation(s)
- Wei Ding
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Qingqing Li
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Benyong Han
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Yongteng Zhao
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | | | - Delu Ning
- Yunnan Academy of Forestry, Kunming 650051, China
| | - Ting Ma
- Yunnan Academy of Forestry, Kunming 650051, China
| | - Xuya Yu
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China.
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22
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Song X, Zhao Y, Li T, Han B, Zhao P, Xu JW, Yu X. Enhancement of lipid accumulation in Monoraphidium sp. QLY-1 by induction of strigolactone. BIORESOURCE TECHNOLOGY 2019; 288:121607. [PMID: 31176945 DOI: 10.1016/j.biortech.2019.121607] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 05/30/2019] [Accepted: 05/31/2019] [Indexed: 06/09/2023]
Abstract
In this study, the effects of strigolactone (SL) on the biomass, lipid content, biochemical properties, and gene transcription of Monoraphidium sp. QLY-1 were examined. The lipid content and lipid productivity increased by 61% and 55% in QLY-1 under 1 μM SL induction compared to the control group, respectively. SL also upregulated the levels of endogenous NO and Ca2+ and lipid biosynthesis gene transcription. Subsequently, the relationship between Ca2+ and nitric oxide (NO) in the regulation of cell growth and lipid accumulation of QLY-1 under SL induction conditions was analysed. An increase in endogenous Ca2+ regulated cell growth and lipid biosynthesis by modulating the levels of NO and lipid biosynthesis-related gene expression. Collectively, this study provided a valuable approach for biofuel production from microalgae under SL induction and demonstrated that there is crucial crosstalk between the Ca2+ and NO signalling in the manipulation of lipid biosynthesis in microalgae under SL treatment.
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Affiliation(s)
- Xueting Song
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Yongteng Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Tao Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Benyong Han
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Peng Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Jun-Wei Xu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Xuya Yu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China.
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23
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Zhu S, Feng S, Xu Z, Qin L, Shang C, Feng P, Wang Z, Yuan Z. Cultivation of Chlorella vulgaris on unsterilized dairy-derived liquid digestate for simultaneous biofuels feedstock production and pollutant removal. BIORESOURCE TECHNOLOGY 2019; 285:121353. [PMID: 31005641 DOI: 10.1016/j.biortech.2019.121353] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 04/12/2019] [Accepted: 04/13/2019] [Indexed: 06/09/2023]
Abstract
In order to assess viability of microalgae cultivation using unsterilized dairy-derived liquid digestate (DLD) for simultaneous biofuels feedstock production and contaminant removal, four DLD concentrations (25%, 50%, 75% and 100%) were used to grow Chlorella vulgaris in batch photobioreactors (PBRs). The 25% DLD was an ideal alternative medium in that high growth rate (0.69 d-1), high lipid productivity (112.9 mg L-1 d-1) as well as high nutrient removal were attained. The high DLD concentration caused inhibition of microalgal growth, where COD was more inhibitive than ammonium. The presence of bacteria did not influence microalgae production because of limited growth. Microalgal growth reduced the richness and diversity of bacterial community. Furthermore, the species of Bacteroidetes, Candidatus Saccharibacteria, and Chlamydiae rather than Proteobacteria benefited microalgal-bacterial symbiosis. These findings contribute to better application of microalgal-bacterial system for large-scale microalgae cultivation as well as environmental sustainability.
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Affiliation(s)
- Shunni Zhu
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
| | - Siran Feng
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhongbin Xu
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Lei Qin
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Changhua Shang
- College of Life Science, Guangxi Normal University, Guilin, Guangxi 541006, China
| | - Pingzhong Feng
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Zhongming Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Zhenhong Yuan
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
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24
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Ding W, Cui J, Zhao Y, Han B, Li T, Zhao P, Xu JW, Yu X. Enhancing Haematococcus pluvialis biomass and γ-aminobutyric acid accumulation by two-step cultivation and salt supplementation. BIORESOURCE TECHNOLOGY 2019; 285:121334. [PMID: 30991185 DOI: 10.1016/j.biortech.2019.121334] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 04/08/2019] [Accepted: 04/10/2019] [Indexed: 06/09/2023]
Abstract
The primary goal of this study was to assess the roles of chemical factors and bioprocess strategies on a mixotrophic culture of the microalga Haematococcus pluvialis during γ-aminobutyric acid (GABA) production. A two-stage strategy was used to increase the biomass and GABA accumulation of H. pluvialis. In stage I, mixotrophic growth of H. pluvialis in the presence of fulvic acid (FA) produced a high biomass (1.84 g L-1) with a GABA content of 25.45 mg g-1. Furthermore, a maximum GABA content of 38.57 mg g-1 was obtained when cells were cultured with 0.4 g L-1 NaCl under photoautotrophic conditions in stage II, whereas the carbohydrate content of cells sharply decreased from 26.68 to 18.22%. In addition, salt stress upregulated the expression of the gad and cam genes. The results of this study demonstrate an efficient strategy to produce GABA from the microalga H. pluvialis.
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Affiliation(s)
- Wei Ding
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Jing Cui
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Yongteng Zhao
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Benyong Han
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Tao Li
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Peng Zhao
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Jun-Wei Xu
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Xuya Yu
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China.
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25
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Salama ES, Govindwar SP, Khandare RV, Roh HS, Jeon BH, Li X. Can Omics Approaches Improve Microalgal Biofuels under Abiotic Stress? TRENDS IN PLANT SCIENCE 2019; 24:611-624. [PMID: 31085124 DOI: 10.1016/j.tplants.2019.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 03/27/2019] [Accepted: 04/11/2019] [Indexed: 06/09/2023]
Abstract
Microalgae hold the promise of an inexpensive and sustainable source of biofuels. The existing microalgal cultivation technologies need significant improvement to outcompete other biofuel sources such as terrestrial plants. Application of 'algomics' approaches under different abiotic stress conditions could be an effective strategy for optimization of microalgal growth and production of high-quality biofuels. In this review, we discuss the roles of omics in understanding genome structure and biocomponents metabolism in various microalgal species to optimize sustainable biofuel production. Application of individual and integrated omics revealed that genes and metabolic pathways of microalgae have been altered under multiple stress conditions, resulting in an increase in biocomponents, providing a research platform for expansion of genetic engineering studies in microalgal strains.
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Affiliation(s)
- El-Sayed Salama
- MOE, Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, 730000, Gansu Province, PR China; Department of Occupational and Environmental Health, School of Public Health, Lanzhou University, Lanzhou 730000, Gansu Province, PR China
| | - Sanjay P Govindwar
- Department of Earth Resources and Environmental Engineering, Hanyang University, Seoul, 04763, South Korea
| | - Rahul V Khandare
- Amity Institute of Biotechnology, Amity University, Mumbai, 410206, India
| | - Hyun-Seog Roh
- Department of Environmental Engineering, Yonsei University, Wonju, Gangwon-do 220-710, South Korea
| | - Byong-Hun Jeon
- Department of Earth Resources and Environmental Engineering, Hanyang University, Seoul, 04763, South Korea.
| | - Xiangkai Li
- MOE, Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, 730000, Gansu Province, PR China.
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26
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Li Y, Sun H, Wu T, Fu Y, He Y, Mao X, Chen F. Storage carbon metabolism of Isochrysis zhangjiangensis under different light intensities and its application for co-production of fucoxanthin and stearidonic acid. BIORESOURCE TECHNOLOGY 2019; 282:94-102. [PMID: 30852337 DOI: 10.1016/j.biortech.2019.02.127] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/26/2019] [Accepted: 02/28/2019] [Indexed: 05/06/2023]
Abstract
This study explored the co-production of fucoxanthin and stearidonic acid from Isochrysis zhangjiangensis by investigating its carbon metabolism under different light intensities. Results showed high light inhibited the synthesis of fucoxanthin and stearidonic acid, while promoted cell growth and enhanced cellular lipid content compared with low light, achieving 2.4 g/L and 28.55%, respectively. Low light accelerated the accumulation of fucoxanthin and stearidonic acid, which obtained 23.29 mg/g and 17.16% (of total fatty acid). In combination with the molecular analysis, low light redirected carbon skeletons into glyceraldehyde-3-phosphate and diverted into carotenoid especially fucoxanthin. While, high light redistributed the skeletons to Malonyl CoA, citrate and α-Ketoglutarate and then oriented into lipid metabolism. The highest fucoxanthin and stearidonic acid productivity was 2.94 mg L-1 d-1 and 4.33 mg L-1 d-1, respectively, which revealed I. zhanjiangensis is a potential strain for the co-production of fucoxanthin and stearidonic acid.
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Affiliation(s)
- Yuelian Li
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Han Sun
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China; Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Tao Wu
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Yunlei Fu
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Yongjin He
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Xuemei Mao
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China; Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Feng Chen
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China; Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China.
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27
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Dong X, Zhao Y, Li T, Huang L, Zhao P, Xu JW, Ma H, Yu X. Enhancement of lipid production and nutrient removal of Monoraphidium sp. FXY-10 by combined melatonin and molasses wastewater treatment. J Taiwan Inst Chem Eng 2019. [DOI: 10.1016/j.jtice.2019.03.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Liu J, Sun Z, Mao X, Gerken H, Wang X, Yang W. Multiomics analysis reveals a distinct mechanism of oleaginousness in the emerging model alga Chromochloris zofingiensis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 98:1060-1077. [PMID: 30828893 DOI: 10.1111/tpj.14302] [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: 10/30/2018] [Revised: 02/15/2019] [Accepted: 02/19/2019] [Indexed: 06/09/2023]
Abstract
Chromochloris zofingiensis, featured due to its capability to simultaneously synthesize triacylglycerol (TAG) and astaxanthin, is emerging as a leading candidate alga for production uses. To better understand the oleaginous mechanism of this alga, we conducted a multiomics analysis by systematically integrating time-resolved transcriptomes, lipidomes and metabolomes in response to nitrogen deprivation. The data analysis unraveled the distinct mechanism of TAG accumulation, which involved coordinated stimulation of multiple biological processes including supply of energy and reductants, carbon reallocation from protein and starch, and 'pushing' and 'pulling' carbon to TAG synthesis. Unlike the model alga Chlamydomonas, de novo fatty acid synthesis in C. zofingiensis was promoted, together with enhanced turnover of both glycolipids and phospholipids, supporting the drastic need of acyls for TAG assembly. Moreover, genomewide analysis identified many key functional enzymes and transcription factors that had engineering potential for TAG modulation. Two genes encoding glycerol-3-phosphate acyltransferase (GPAT), the first committed enzyme for TAG assembly, were found in the C. zofingiensis genome; in vivo functional characterization revealed that extrachloroplastic GPAT instead of chloroplastic GPAT played a central role in TAG synthesis. These findings illuminate distinct oleaginousness mechanisms in C. zofingiensis and pave the way towards rational manipulation of this alga to becone an emerging model for trait improvements.
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Affiliation(s)
- Jin Liu
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871, China
| | - Zheng Sun
- International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, 201306, China
| | - Xuemei Mao
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871, China
| | - Henri Gerken
- School of Sustainable Engineering and the Built Environment, Arizona State University Polytechnic campus, Mesa, AZ, 85212, USA
| | - Xiaofei Wang
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871, China
| | - Wenqiang Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
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Mao X, Wu T, Kou Y, Shi Y, Zhang Y, Liu J. Characterization of type I and type II diacylglycerol acyltransferases from the emerging model alga Chlorella zofingiensis reveals their functional complementarity and engineering potential. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:28. [PMID: 30792816 PMCID: PMC6371474 DOI: 10.1186/s13068-019-1366-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 01/30/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND The green alga Chlorella zofingiensis has been recognized as an industrially relevant strain because of its robust growth under multiple trophic conditions and the potential for simultaneous production of triacylglycerol (TAG) and the high-value keto-carotenoid astaxanthin. Nevertheless, the mechanism of TAG synthesis remains poorly understood in C. zofingiensis. Diacylglycerol acyltransferase (DGAT) is thought to catalyze the committed step of TAG assembly in the Kennedy pathway. C. zofingiensis genome is predicted to possess eleven putative DGAT-encoding genes, the greatest number ever found in green algae, pointing to the complexity of TAG assembly in the alga. RESULTS The transcription start site of C. zofingiensis DGATs was determined by 5'-rapid amplification of cDNA ends (RACE), and their coding sequences were cloned and verified by sequencing, which identified ten DGAT genes (two type I DGATs designated as CzDGAT1A and CzDGAT1B, and eight type II DGATs designated as CzDGTT1 through CzDGTT8) and revealed that the previous gene models of seven DGATs were incorrect. Function complementation in the TAG-deficient yeast strain confirmed the functionality of most DGATs, with CzDGAT1A and CzDGTT5 having the highest activity. In vitro DGAT assay revealed that CzDGAT1A and CzDGTT5 preferred eukaryotic and prokaryotic diacylglycerols (DAGs), respectively, and had overlapping yet distinctive substrate specificity for acyl-CoAs. Subcellular co-localization experiment in tobacco leaves indicated that both CzDGAT1A and CzDGTT5 were localized at endoplasmic reticulum (ER). Upon nitrogen deprivation, TAG was drastically induced in C. zofingiensis, accompanied by a considerable up-regulation of CzDGAT1A and CzDGTT5. These two genes were probably regulated by the transcription factors (TFs) bZIP3 and MYB1, as suggested by the yeast one-hybrid assay and expression correlation. Moreover, heterologous expression of CzDGAT1A and CzDGTT5 promoted TAG accumulation and TAG yield in different hosts including yeast and oleaginous alga. CONCLUSIONS Our study represents a pioneering work on the characterization of both type I and type II C. zofingiensis DGATs by systematically integrating functional complementation, in vitro enzymatic assay, subcellular localization, yeast one-hybrid assay and overexpression in yeast and oleaginous alga. These results (1) update the gene models of C. zofingiensis DGATs, (2) shed light on the mechanism of oleaginousness in which CzDGAT1A and CzDGTT5, have functional complementarity and probably work in collaboration at ER contributing to the abundance and complexity of TAG, and (3) provide engineering targets for future trait improvement via rational manipulation of this alga as well as other industrially relevant ones.
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Affiliation(s)
- Xuemei Mao
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Tao Wu
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Yaping Kou
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Ying Shi
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Yu Zhang
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Jin Liu
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
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Koh HG, Kang NK, Jeon S, Shin SE, Jeong BR, Chang YK. Heterologous synthesis of chlorophyll b in Nannochloropsis salina enhances growth and lipid production by increasing photosynthetic efficiency. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:122. [PMID: 31114631 PMCID: PMC6515666 DOI: 10.1186/s13068-019-1462-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 05/04/2019] [Indexed: 05/16/2023]
Abstract
BACKGROUND Chlorophylls play important roles in photosynthesis, and thus are critical for growth and related metabolic pathways in photosynthetic organisms. They are particularly important in microalgae, emerging as the next generation feedstock for biomass and biofuels. Nannochloropsis are industrial microalgae for these purposes, but are peculiar in that they lack accessory chlorophylls. In addition, the localization of heterologous proteins to the chloroplast of Nannochloropsis has not been fully studied, due to the secondary plastid surrounded by four membranes. This study addressed questions of correct localization and functional benefits of heterologous expression of chlorophyllide a oxygenase from Chlamydomonas (CrCAO) in Nannochloropsis. RESULTS We cloned CrCAO from Chlamydomonas, which catalyzes oxidation of Chla producing Chlb, and overexpressed it in N. salina to reveal effects of the heterologous Chlb for photosynthesis, growth, and lipid production. For correct localization of CrCAO into the secondary plastid in N. salina, we added the signal-recognition sequence and the transit peptide (cloned from an endogenous chloroplast-localized protein) to the N terminus of CrCAO. We obtained two transformants that expressed CrCAO and produced Chlb. They showed improved growth under medium light (90 μmol/m2/s) conditions, and their photosynthetic efficiency was increased compared to WT. They also showed increased expression of certain photosynthetic proteins, accompanied by an increased maximum electron-transfer rate up to 15.8% and quantum yields up to 17%, likely supporting the faster growth. This improved growth resulted in increased biomass production, and more importantly lipid productivity particularly with medium light. CONCLUSIONS We demonstrated beneficial effects of heterologous expression of CrCAO in Chlb-less organism N. salina, where the newly produced Chlb enhanced photosynthesis and growth. Accordingly, transformants showed improved production of biomass and lipids, important traits of microalgae from the industrial perspectives. Our transformants are the first Nannochloropsis cells that produced Chlb in the whole evolutionary path. We also succeeded in delivering a heterologous protein into the secondary plastid for the first time in Nannochloropsis. Taken together, our data showed that manipulation of photosynthetic pigments, including Chlb, can be employed in genetic improvements of microalgae for production of biofuels and other biomaterials.
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Affiliation(s)
- Hyun Gi Koh
- Advanced Biomass R&D Center, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Nam Kyu Kang
- Advanced Biomass R&D Center, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Present Address: Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Seungjib Jeon
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Sung-Eun Shin
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Present Address: LG Chem, 188 Munji-ro, Yuseong-gu, Daejeon, 34122 Republic of Korea
| | - Byeong-ryool Jeong
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Yong Keun Chang
- Advanced Biomass R&D Center, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
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31
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He Y, Wu T, Sun H, Sun P, Liu B, Luo M, Chen F. Comparison of fatty acid composition and positional distribution of microalgae triacylglycerols for human milk fat substitutes. ALGAL RES 2019. [DOI: 10.1016/j.algal.2018.11.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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32
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Enhanced lipid content in Chlorella sp. FC2 IITG via high energy irradiation mutagenesis. KOREAN J CHEM ENG 2018. [DOI: 10.1007/s11814-018-0180-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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33
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Zhao W, Sun H, Ren Y, Wu T, He Y, Chen F. Chlorella zofingiensis as a promising strain in wastewater treatment. BIORESOURCE TECHNOLOGY 2018; 268:286-291. [PMID: 30086455 DOI: 10.1016/j.biortech.2018.07.144] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 07/27/2018] [Accepted: 07/28/2018] [Indexed: 06/08/2023]
Abstract
This study was conducted to evaluate the efficiency of treatment by C. zofingiensis, C. vulgaris and Scenedesmus sp. in terms of nutrient loading, lipid productivity and the activity of photosystem II. Results from nutrient loading suggested that the nitrogen loading of C. zofingiensis at 0.406 mg/L/h was higher than C. vulgaris and Scenedesmus sp., and the phosphorus loading of C. zofingiensis at 0.075 mg/L/h was higher than C. vulgaris. During the treating process, C. zofingiensis accumulated lipid with higher productivity of 26.57 mg/L/d than C. vulgaris and Scenedesmus sp. In combination with photosynthetic efficiency, C. zofingiensis possessed superior trophic transfer efficiency and absorption capability, even in worse environmental conditions. C. zofingiensis, therefore, exhibited the promising application prospect in wastewater treatment.
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Affiliation(s)
- Weiyang Zhao
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Han Sun
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Yuanyuan Ren
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Tao Wu
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Yongjin He
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Feng Chen
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China.
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34
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Zhao Y, Yue C, Ding W, Li T, Xu JW, Zhao P, Ma H, Yu X. Butylated hydroxytoluene induces astaxanthin and lipid production in Haematococcus pluvialis under high-light and nitrogen-deficiency conditions. BIORESOURCE TECHNOLOGY 2018; 266:315-321. [PMID: 29982053 DOI: 10.1016/j.biortech.2018.06.111] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/29/2018] [Accepted: 06/30/2018] [Indexed: 05/20/2023]
Abstract
The aim of this study was to investigate the effects of butylated hydroxytoluene (BHT) on the production of astaxanthin and lipids in Haematococcus pluvialis LUGU under high-light and nitrogen-deficiency conditions. Astaxanthin and lipid contents were increased by 71.13% and 10.71%, respectively, in algal cells treated with 2 mg L-1 BHT. The maximal contents of astaxanthin and lipids were 3.17% and 46%, respectively. The levels of reactive oxygen species (ROS) in the presence of BHT were lower than in the control, and this effect involved strong activation of several antioxidases. Additionally, BHT application upregulated endogenous nitric oxide (NO) production. These results showed that this approach is useful for stimulating production of astaxanthin and lipids in H. pluvialis and that exogenous BHT induces astaxanthin and lipid production, which is responsible for the signalling molecule responses against abiotic stress conditions in H. pluvialis.
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Affiliation(s)
- Yongteng Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Chenchen Yue
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Wei Ding
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Tao Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Jun-Wei Xu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Peng Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Huixian Ma
- School of Foreign Languages, Kunming University, Kunming 650200, China
| | - Xuya Yu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China.
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35
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Sun H, Mao X, Wu T, Ren Y, Chen F, Liu B. Novel insight of carotenoid and lipid biosynthesis and their roles in storage carbon metabolism in Chlamydomonas reinhardtii. BIORESOURCE TECHNOLOGY 2018; 263:450-457. [PMID: 29772507 DOI: 10.1016/j.biortech.2018.05.035] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 05/08/2018] [Accepted: 05/09/2018] [Indexed: 05/26/2023]
Abstract
Revenues of carotenoid and lipid biosynthesis under excess light and nitrogen starvation were firstly analyzed for the increased biomass value through carbon metabolism analysis. The results suggested excess light and nitrogen starvation resulted in carbon partitioning among protein, starch, lipid and carotenoid. Nitrogen starvation promoted more cellular lipid content than excess light, while excess light promoted carotenoid and polyunsaturated fatty acid accumulation. In the molecular level, the stresses redirected carbon skeletons into the central metabolite of pyruvate and oriented into starch and lipid as the primary and secondary carbon storage, respectively. Economic estimation revealed nitrogen starvation potentially increased 14.76 × 10-6 and 72.11 × 10-6 $/g revenues of biofuel production at per batch and cell weight scales, respectively. Excess light could increase 63.90 × 10-6 and 19.21 × 10-6 $/g at per cell weight scale of lipid and carotenoid, respectively. In combination with metabolism analysis, conversion procedure of process-compatible products was divided into four phases.
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Affiliation(s)
- Han Sun
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Xuemei Mao
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Tao Wu
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Yuanyuan Ren
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Feng Chen
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Bin Liu
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China.
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36
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Melatonin enhances astaxanthin accumulation in the green microalga Haematococcus pluvialis by mechanisms possibly related to abiotic stress tolerance. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.05.021] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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37
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Zhao Y, Li D, Xu JW, Zhao P, Li T, Ma H, Yu X. Melatonin enhances lipid production in Monoraphidium sp. QLY-1 under nitrogen deficiency conditions via a multi-level mechanism. BIORESOURCE TECHNOLOGY 2018. [PMID: 29536873 DOI: 10.1016/j.biortech.2018.03.014] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In this study, melatonin (MT) promoted lipid accumulation in Monoraphidium sp. QLY-1 under nitrogen deficiency conditions. The lipid accumulation increased 1.22- and 1.36-fold compared with a nitrogen-starved medium and a normal BG-11 medium, respectively. The maximum lipid content was 51.38%. The reactive oxygen species (ROS) level in the presence of melatonin was lower than that in the control group, likely because of the high antioxidant activities. The application of melatonin upregulated the gibberellin acid (GA) production and rbcL and accD expression levels but downregulated the abscisic acid (ABA) content and pepc expression levels. These findings demonstrated that exogenous melatonin could further improve the lipid production in Monoraphidium sp. QLY-1 by regulating antioxidant systems, signalling molecules, and lipid biosynthesis-related gene expression under nitrogen deficiency conditions.
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Affiliation(s)
- Yongteng Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Dafei Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Jun-Wei Xu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Peng Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Tao Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Huixian Ma
- School of Foreign Languages, Kunming University, Kunming 650200, China
| | - Xuya Yu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China.
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38
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Willette S, Gill SS, Dungan B, Schaub TM, Jarvis JM, St. Hilaire R, Omar Holguin F. Alterations in lipidome and metabolome profiles of Nannochloropsis salina in response to reduced culture temperature during sinusoidal temperature and light. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.03.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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39
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Ma X, Yao L, Yang B, Lee YK, Chen F, Liu J. RNAi-mediated silencing of a pyruvate dehydrogenase kinase enhances triacylglycerol biosynthesis in the oleaginous marine alga Nannochloropsis salina. Sci Rep 2017; 7:11485. [PMID: 28904365 PMCID: PMC5597597 DOI: 10.1038/s41598-017-11932-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 08/31/2017] [Indexed: 01/01/2023] Open
Abstract
Oleaginous microalgae have been emerging as the third-generation feedstocks for biofuel production. Genetic manipulation for improving triacylglycerol (TAG) accumulation represents a promising approach towards the economics of microalgal biofuels. Acetyl-CoA, the essential carbon precursor for de novo fatty acid biosynthesis, can be derived from pyruvate catalyzed by pyruvate dehydrogenase, which is negatively regulated by pyruvate dehydrogenase kinase (PDK). In the present study, we characterized a PDK gene (NsPDK) from Nannochloropsis salina. Subcellular localization assay assisted by green fluorescence protein (GFP) fusion indicated the localization of NsPDK in mitochondria of N. salina cells. NsPDK knockdown via RNA interference strategy attenuated NsPDK expression at the mRNA level and its enzymatic activity in vivo, leading to faster TAG accumulation without compromising cell growth under high light stress conditions. Interestingly, the TAG increase was accompanied by a decline in membrane polar lipids. NsPDK knockdown also altered fatty acid profile in N. salina. Furthermore, transcriptional analysis suggested that the carbon metabolic pathways might be influenced by NsPDK knockdown leading to diverted carbon flux towards TAG synthesis. Taken together, our results demonstrate the role of NsPDK in regulating TAG accumulation and provide valuable insights into future manipulation of oleaginous microalgae for improving biofuel production.
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Affiliation(s)
- Xiaonian Ma
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871, China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871, China
| | - Lina Yao
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore, Singapore
| | - Bo Yang
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871, China
| | - Yuan Kun Lee
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore, Singapore
| | - Feng Chen
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871, China.
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871, China.
| | - Jin Liu
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871, China.
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871, China.
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40
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He Y, Qiu C, Guo Z, Huang J, Wang M, Chen B. Production of new human milk fat substitutes by enzymatic acidolysis of microalgae oils from Nannochloropsis oculata and Isochrysis galbana. BIORESOURCE TECHNOLOGY 2017; 238:129-138. [PMID: 28433900 DOI: 10.1016/j.biortech.2017.04.041] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 04/08/2017] [Accepted: 04/10/2017] [Indexed: 06/07/2023]
Abstract
Human milk fat substitutes (HMFs) with four kinds of n-3 fatty acid for infant formula were firstly synthesized using triacylglycerols (TAGs) from Nannochloropsis oculata rich in PA at the sn-2 position and free fatty acids (FFAs) from Isochrysis galbana rich in n-3 polyunsaturated fatty acids (n-3 PUFAs-ALA/SDA/DHA) via solvent-free acidolysis with Novozym 435, Lipozyme 435, TL-IM and RM-IM as biocatalysts. The results show that the resulting HMFs contain total n-3 PUFA of 13.92-17.12% and PA of 59.38-68.13% at the sn-2 position under the optimal conditions (mole ratio FFAs/TAG 3:1, 60°C (Novozym 435 and Lipozyme TL-IM) and 50°C (Lipozyme 435 and RM-IM), lipase loading 10%, reaction time 24h). Moreover, among the tested enzymes, Lipozyme 435, TL-IM, and RM-IM display the fatty acid selectivity towards SDA, LA and ALA, and OA, respectively. Overall, the examined lipases are promising biocatalysts for producing high-value microalgal HMFs in a cost-effective manner.
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Affiliation(s)
- Yongjin He
- College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Changyang Qiu
- College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Zheng Guo
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Jian Huang
- College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Mingzi Wang
- College of Life Science, Fujian Normal University, Fuzhou 350117, China; Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou 350117, China
| | - Bilian Chen
- College of Life Science, Fujian Normal University, Fuzhou 350117, China; Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou 350117, China.
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41
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Li D, Zhao Y, Ding W, Zhao P, Xu JW, Li T, Ma H, Yu X. A strategy for promoting lipid production in green microalgae Monoraphidium sp. QLY-1 by combined melatonin and photoinduction. BIORESOURCE TECHNOLOGY 2017; 235:104-112. [PMID: 28365337 DOI: 10.1016/j.biortech.2017.03.114] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/15/2017] [Accepted: 03/20/2017] [Indexed: 05/03/2023]
Abstract
Microalgae lipids are potential candidates for the production of renewable biodiesel. The combination of plant hormones and two-step cultivation regulates lipid production in microalgae. A strategy for promoting lipid accumulation in Monoraphidium sp. QLY-1 by combining exogenous melatonin (MT) and photoinduction was developed. The effects of melatonin on the lipid content, reactive oxygen species (ROS), and activities of three key fatty acid biosynthetic enzyme in Monoraphidium sp. QLY-1 were investigated. The lipid content increased by 1.32-fold under 1μM melatonin treatment. The maximum lipid content achieved was 49.6%. However, the protein and carbohydrate contents decreased rapidly from 57.21% to 47.96% and from 53.4% to 37.71%, respectively. Biochemical and physiological analyses suggested that the ROS and lipid biosynthesis-related enzyme activities correlated with increased lipid accumulation under photo-melatonin induction conditions.
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Affiliation(s)
- Dafei Li
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Yongteng Zhao
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Wei Ding
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Peng Zhao
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Jun-Wei Xu
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Tao Li
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Huixian Ma
- School of Foreign Languages, Kunming University, Kunming 650200, China
| | - Xuya Yu
- Faculty of Life Sciences and Technology, Kunming University of Science and Technology, Kunming 650500, China.
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42
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León-Saiki GM, Remmers IM, Martens DE, Lamers PP, Wijffels RH, van der Veen D. The role of starch as transient energy buffer in synchronized microalgal growth in Acutodesmus obliquus. ALGAL RES 2017. [DOI: 10.1016/j.algal.2017.05.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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43
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44
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Schüler LM, Schulze PS, Pereira H, Barreira L, León R, Varela J. Trends and strategies to enhance triacylglycerols and high-value compounds in microalgae. ALGAL RES 2017. [DOI: 10.1016/j.algal.2017.05.025] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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45
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Che R, Huang L, Xu JW, Zhao P, Li T, Ma H, Yu X. Effect of fulvic acid induction on the physiology, metabolism, and lipid biosynthesis-related gene transcription of Monoraphidium sp. FXY-10. BIORESOURCE TECHNOLOGY 2017; 227:324-334. [PMID: 28042988 DOI: 10.1016/j.biortech.2016.12.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Revised: 12/02/2016] [Accepted: 12/03/2016] [Indexed: 05/03/2023]
Abstract
Fulvic acid (FA) triggers lipid accumulation in Monoraphidium sp. FXY-10, which can produce biofuels. Therefore, the metabolism shift and gene expression changes influenced by fulvic acid should be investigated. In this study, lipid and protein contents increased rapidly from 44.6% to 54.3% and from 31.4% to 39.7% under FA treatment, respectively. By contrast, carbohydrate content sharply declined from 49.5% to 32.5%. The correlation between lipid content and gene expression was also analyzed. Results revealed that accD, ME, and GPAT genes were significantly correlated with lipid accumulation. These genes could likely influence lipid accumulation and could be selected as modification candidates. These results demonstrated that FA significantly increased microalgal lipid accumulation by changing the intracellular reactive oxygen species, gene expression, and enzyme activities of acetyl-CoA carboxylase, malic enzyme, and phosphoenolpyruvate carboxylase.
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Affiliation(s)
- Raoqiong Che
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Li Huang
- Institute of Chemical Industry, Kunming Metallurgy College, Kunming, China
| | - Jun-Wei Xu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Peng Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Tao Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Huixian Ma
- School of Foreign Languages, Kunming University, Kunming 650200, China
| | - Xuya Yu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China.
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46
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Yang B, Liu J, Ma X, Guo B, Liu B, Wu T, Jiang Y, Chen F. Genetic engineering of the Calvin cycle toward enhanced photosynthetic CO 2 fixation in microalgae. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:229. [PMID: 29034004 PMCID: PMC5629779 DOI: 10.1186/s13068-017-0916-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Accepted: 09/26/2017] [Indexed: 05/18/2023]
Abstract
BACKGROUND Photosynthetic microalgae are emerging as potential biomass feedstock for sustainable production of biofuels and value-added bioproducts. CO2 biomitigation through these organisms is considered as an eco-friendly and promising alternative to the existing carbon sequestration methods. Nonetheless, the inherent relatively low photosynthetic capacity of microalgae has hampered the practical use of this strategy for CO2 biomitigation applications. RESULTS Here, we demonstrate the feasibility of improving photosynthetic capacity by the genetic manipulation of the Calvin cycle in the typical green microalga Chlorella vulgaris. Firstly, we fused a plastid transit peptide to upstream of the enhanced green fluorescent protein (EGFP) and confirmed its expression in the chloroplast of C. vulgaris. Then we introduced the cyanobacterial fructose 1,6-bisphosphate aldolase, guided by the plastid transit peptide, into C. vulgaris chloroplast, leading to enhanced photosynthetic capacity (~ 1.2-fold) and cell growth. Molecular and physiochemical analyses suggested a possible role for aldolase overexpression in promoting the regeneration of ribulose 1,5-bisphosphate in the Calvin cycle and energy transfer in photosystems. CONCLUSIONS Our work represents a proof-of-concept effort to enhance photosynthetic capacity by the engineering of the Calvin cycle in green microalgae. Our work also provides insights into targeted genetic engineering toward algal trait improvement for CO2 biomitigation uses.
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Affiliation(s)
- Bo Yang
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871 China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Jin Liu
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871 China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
- Singapore-Peking University Research Centre for a Sustainable Low-Carbon Future, CREATE Tower, Singapore, 138602 Singapore
| | - Xiaonian Ma
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871 China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Bingbing Guo
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871 China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Bin Liu
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871 China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Tao Wu
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871 China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Yue Jiang
- Runke Bioengineering Co., Ltd., Zhangzhou, 363502 China
| | - Feng Chen
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, 100871 China
- BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
- Singapore-Peking University Research Centre for a Sustainable Low-Carbon Future, CREATE Tower, Singapore, 138602 Singapore
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Choudhary P, Prajapati SK, Kumar P, Malik A, Pant KK. Development and performance evaluation of an algal biofilm reactor for treatment of multiple wastewaters and characterization of biomass for diverse applications. BIORESOURCE TECHNOLOGY 2017; 224:276-284. [PMID: 27818159 DOI: 10.1016/j.biortech.2016.10.078] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 10/22/2016] [Accepted: 10/25/2016] [Indexed: 06/06/2023]
Abstract
A modified algal biofilm reactor (ABR) was developed and assessed for high biomass productivity and treatment potential using variable strength wastewaters with accumulation of specialized bio-products. The nonwoven spun bond fabric (70GSM) was selected as suitable biofilm support on the basis of attachment efficiency, durability and ease of harvesting. The biomass productivity achieved by ABR biofilms were 4gm-2d-1, 3.64gm-2d-1 and 3.10gm-2d-1 when grown in livestock wastewater (LSW), domestic grey water (DGW) and anaerobically digested slurry (ADS), respectively. Detailed characterization of wastewater grown biomass showed specific distribution of biomolecules into high lipid (38%) containing biomass (DGW grown) and high protein (44%) biomass (LSW and ADS grown). The feasibility assessment of ABR in terms of net energy return (>1) favored its application in an integrated system for treatment and recycling of rural wastewaters with simultaneous production of biomethane, livestock feed supplement and bio fertilizers.
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Affiliation(s)
- Poonam Choudhary
- Applied Microbiology Laboratory, Centre for Rural Development and Technology, Indian Institute of Technology (IIT) Delhi, Hauz Khas, New Delhi 110016, India; Chemical Engineering Department, Indian Institute of Technology (IIT) Delhi, Hauz Khas, New Delhi 110016, India
| | - Sanjeev Kumar Prajapati
- Biochemical Engineering and Bioenergy Lab (BEBL), Division of Biological Sciences and Engineering, Netaji Subhas Institute of Technology Delhi, Dwarka Sector-3, New Delhi 110078, India
| | - Pushpendar Kumar
- Applied Microbiology Laboratory, Centre for Rural Development and Technology, Indian Institute of Technology (IIT) Delhi, Hauz Khas, New Delhi 110016, India
| | - Anushree Malik
- Applied Microbiology Laboratory, Centre for Rural Development and Technology, Indian Institute of Technology (IIT) Delhi, Hauz Khas, New Delhi 110016, India.
| | - Kamal K Pant
- Chemical Engineering Department, Indian Institute of Technology (IIT) Delhi, Hauz Khas, New Delhi 110016, India
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Wei H, Shi Y, Ma X, Pan Y, Hu H, Li Y, Luo M, Gerken H, Liu J. A type-I diacylglycerol acyltransferase modulates triacylglycerol biosynthesis and fatty acid composition in the oleaginous microalga, Nannochloropsis oceanica. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:174. [PMID: 28694845 PMCID: PMC5499063 DOI: 10.1186/s13068-017-0858-1] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 06/27/2017] [Indexed: 05/03/2023]
Abstract
BACKGROUND Photosynthetic oleaginous microalgae are considered promising feedstocks for biofuels. The marine microalga, Nannochloropsis oceanica, has been attracting ever-increasing interest because of its fast growth, high triacylglycerol (TAG) content, and available genome sequence and genetic tools. Diacylglycerol acyltransferase (DGAT) catalyzes the last and committed step of TAG biosynthesis in the acyl-CoA-dependent pathway. Previous studies have identified 13 putative DGAT-encoding genes in the genome of N. oceanica, but the functional role of DGAT genes, especially type-I DGAT (DGAT1), remains ambiguous. RESULTS Nannochloropsis oceanica IMET1 possesses two DGAT1 genes: NoDGAT1A and NoDGAT1B. Functional complementation demonstrated the capability of NoDGAT1A rather than NoDGAT1B to restore TAG synthesis in a TAG-deficient yeast strain. In vitro DGAT assays revealed that NoDGAT1A preferred saturated/monounsaturated acyl-CoAs and eukaryotic diacylglycerols (DAGs) for TAG synthesis, while NoDGAT1B had no detectable enzymatic activity. Assisted with green fluorescence protein (GFP) fusion, fluorescence microscopy analysis indicated the localization of NoDGAT1A in the chloroplast endoplasmic reticulum (cER) of N. oceanica. NoDGAT1A knockdown caused ~25% decline in TAG content upon nitrogen depletion, accompanied by the reduced C16:0, C18:0, and C18:1 in TAG sn-1/sn-3 positions and C18:1 in the TAG sn-2 position. NoDGAT1A overexpression, on the other hand, led to ~39% increase in TAG content upon nitrogen depletion, accompanied by the enhanced C16:0 and C18:1 in the TAG sn-1/sn-3 positions and C18:1 in the TAG sn-2 position. Interestingly, NoDGAT1A overexpression also promoted TAG accumulation (by ~2.4-fold) under nitrogen-replete conditions without compromising cell growth, and TAG yield of the overexpression line reached 0.49 g L-1 at the end of a 10-day batch culture, 47% greater than that of the control line. CONCLUSIONS Taken together, our work demonstrates the functional role of NoDGAT1A and sheds light on the underlying mechanism for the biosynthesis of various TAG species in N. oceanica. NoDGAT1A resides likely in cER and prefers to transfer C16 and C18 saturated/monounsaturated fatty acids to eukaryotic DAGs for TAG assembly. This work also provides insights into the rational genetic engineering of microalgae by manipulating rate-limiting enzymes such as DGAT to modulate TAG biosynthesis and fatty acid composition for biofuel production.
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Affiliation(s)
- Hehong Wei
- Institute for Food and Bioresource Engineering, Department of Energy and Resources Engineering and BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Ying Shi
- Institute for Food and Bioresource Engineering, Department of Energy and Resources Engineering and BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Xiaonian Ma
- Institute for Food and Bioresource Engineering, Department of Energy and Resources Engineering and BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
| | - Yufang Pan
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072 China
| | - Hanhua Hu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072 China
| | - Yantao Li
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science and University of Maryland Baltimore County, Baltimore, MA 21202 USA
| | - Ming Luo
- Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650 China
| | - Henri Gerken
- School of Sustainable Engineering and the Built Environment, Arizona State University Polytechnic campus, Mesa, AZ 85212 USA
| | - Jin Liu
- Institute for Food and Bioresource Engineering, Department of Energy and Resources Engineering and BIC-ESAT, College of Engineering, Peking University, Beijing, 100871 China
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