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Bora A, Thondi Rajan AS, Ponnuchamy K, Muthusamy G, Alagarsamy A. Microalgae to bioenergy production: Recent advances, influencing parameters, utilization of wastewater - A critical review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 946:174230. [PMID: 38942321 DOI: 10.1016/j.scitotenv.2024.174230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 06/12/2024] [Accepted: 06/21/2024] [Indexed: 06/30/2024]
Abstract
Fossil fuel limitations and their influence on climate change through atmospheric greenhouse gas emissions have made the excessive use of fossil fuels widely recognized as unsustainable. The high lipid content, carbon-neutral nature and potential as a biofuel source have made microalgae a subject of global study. Microalgae are a promising supply of biomass for third-generation biofuels production since they are renewable. They have the potential to produce significant amounts of biofuel and are considered a sustainable alternative to non-renewable energy sources. Microalgae are currently incapable to synthesize algal biofuel on an extensive basis in a sustainable manner, despite their significance in the global production of biofuels. Wastewater contains nutrients (both organic and inorganic) which is essential for the development of microalgae. Microalgae and wastewater can be combined to remediate waste effectively. Wastewater of various kinds such as industrial, agricultural, domestic, and municipal can be used as a substrate for microalgal growth. This process helps reduce carbon dioxide emissions and makes the production of biofuels more cost-effective. This critical review provides a detailed analysis of the utilization of wastewater as a growth medium for microalgal - biofuel production. The review also highlights potential future strategies to improve the commercial production of biofuels from microalgae.
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Affiliation(s)
- Abhispa Bora
- Bioenergy and Bioremediation Laboratory, Department of Microbiology, Alagappa University, Karaikudi 630003, Tamil Nadu, India
| | - Angelin Swetha Thondi Rajan
- Bioenergy and Bioremediation Laboratory, Department of Microbiology, Alagappa University, Karaikudi 630003, Tamil Nadu, India
| | - Kumar Ponnuchamy
- Department of Animal Health and Management, Alagappa University, Karaikudi 630003, Tamil Nadu, India
| | - Govarthanan Muthusamy
- Department of Environmental Engineering, Kyungpook National University, 41566 Daegu, Republic of Korea
| | - Arun Alagarsamy
- Bioenergy and Bioremediation Laboratory, Department of Microbiology, Alagappa University, Karaikudi 630003, Tamil Nadu, India.
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Nabila DS, Chan R, Syamsuri RRP, Nurlilasari P, Wan-Mohtar WAAQI, Ozturk AB, Rossiana N, Doni F. Biobutanol production from underutilized substrates using Clostridium: Unlocking untapped potential for sustainable energy development. CURRENT RESEARCH IN MICROBIAL SCIENCES 2024; 7:100250. [PMID: 38974669 PMCID: PMC11225672 DOI: 10.1016/j.crmicr.2024.100250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/09/2024] Open
Abstract
The increasing demand for sustainable energy has brought biobutanol as a potential substitute for fossil fuels. The Clostridium genus is deemed essential for biobutanol synthesis due to its capability to utilize various substrates. However, challenges in maintaining fermentation continuity and achieving commercialization persist due to existing barriers, including butanol toxicity to Clostridium, low substrate utilization rates, and high production costs. Proper substrate selection significantly impacts fermentation efficiency, final product quality, and economic feasibility in Clostridium biobutanol production. This review examines underutilized substrates for biobutanol production by Clostridium, which offer opportunities for environmental sustainability and a green economy. Extensive research on Clostridium, focusing on strain development and genetic engineering, is essential to enhance biobutanol production. Additionally, critical suggestions for optimizing substrate selection to enhance Clostridium biobutanol production efficiency are also provided in this review. In the future, cost reduction and advancements in biotechnology may make biobutanol a viable alternative to fossil fuels.
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Affiliation(s)
- Devina Syifa Nabila
- Department of Biology, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Jatinangor, West Java 45363, Indonesia
| | - Rosamond Chan
- Department of Biology, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Jatinangor, West Java 45363, Indonesia
| | | | - Puspita Nurlilasari
- Department of Agro-industrial Technology, Faculty of Agro-industrial Technology, Universitas Padjadjaran, Jatinangor, West Java 45363, Indonesia
| | - Wan Abd Al Qadr Imad Wan-Mohtar
- Functional Omics and Bioprocess Development Laboratory, Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Abdullah Bilal Ozturk
- Department of Chemical Engineering, Faculty of Chemical and Metallurgical Engineering, Yildiz Technical University, Esenler, Istanbul 34220, Türkiye
| | - Nia Rossiana
- Department of Biology, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Jatinangor, West Java 45363, Indonesia
| | - Febri Doni
- Department of Biology, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Jatinangor, West Java 45363, Indonesia
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Wang H, Qin L, Qi W, Elshobary M, Wang W, Feng P, Wang Z, Zhu S. Harmony in detoxification: Microalgae unleashing the potential of lignocellulosic pretreatment wastewater for resource utilization. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:171888. [PMID: 38531442 DOI: 10.1016/j.scitotenv.2024.171888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 02/28/2024] [Accepted: 03/20/2024] [Indexed: 03/28/2024]
Abstract
Lignocellulosic biomass is a pivotal renewable resource in biorefinery process, requiring pretreatment, primarily chemical pretreatment, for effective depolymerization and subsequent transformation. This process yields solid residue for saccharification and lignocellulosic pretreatment wastewater (LPW), which comprises sugars and inhibitors such as phenols and furans. This study explored the microalgal capacity to treat LPW, focusing on two key hydrolysate inhibitors: furfural and vanillin, which impact the growth of six green microalgae. Chlorella sorokiniana exhibited higher tolerance to furfural and vanillin. However, both inhibitors hindered the growth of C. sorokiniana and disrupted algal photosynthetic system, with vanillin displaying superior inhibition. A synergistic inhibitory effect (Q < 0.85) was observed with furfural and vanillin on algal growth. Furfural transformation to low-toxic furfuryl alcohol was rapid, yet the addition of vanillin hindered this process. Vanillin stimulated carbohydrate accumulation, with 50.48 % observed in the 0.1 g/L furfural + 0.1 g/L vanillin group. Additionally, vanillin enhanced the accumulation of C16: 0 and C18: 2, reaching 21.71 % and 40.36 %, respectively, with 0.1 g/L vanillin. This study proposed a microalgae-based detoxification and resource utilization approach for LPW, enhancing the comprehensive utilization of lignocellulosic components. The observed biomass modifications also suggested potential applications for biofuel production, contributing to the evolving landscape of sustainable biorefinery processes.
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Affiliation(s)
- Huiying Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China; University of Science and Technology of China, Hefei 230026, PR China
| | - Lei Qin
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
| | - Wei Qi
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China
| | - Mostafa Elshobary
- Botany and Microbiology Department, Faculty of Science, Tanta University, Tanta 31527, Egypt
| | - Wen Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China
| | - Pingzhong Feng
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China
| | - Zhongming Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China
| | - Shunni Zhu
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
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Ro JW, Yothers C, Kendall A, Franz A, Zhang R. Economic and environmental performance of microalgal energy products - A case study exploring circular bioeconomy principles applied to recycled anaerobic digester waste flows. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 358:120802. [PMID: 38599084 DOI: 10.1016/j.jenvman.2024.120802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 03/05/2024] [Accepted: 03/30/2024] [Indexed: 04/12/2024]
Abstract
This study quantifies the financial and environmental impacts of a microalgal bioenergy system that attempts to maximize circular flows by recovering and reusing the carbon, nutrients, and water within the system. The system produces microalgal biomass using liquid digestate of an anaerobic digester that processes 45 metric tons of food waste and generates 28.6 m3 of permeate daily in California, and three energy production scenarios from the biomass are considered: producing biodiesel, electricity, and both. In all scenarios, the resulting energy products delivered only modest reductions in environmental impacts as measured by carbon dioxide equivalent emissions. The carbon intensities (CIs) of biodiesel from this study were 91.0 gCO2e/MJ and 93.3 gCO2e/MJ, which were lower than 94.71 gCO2e/MJ of conventional petroleum diesel, and the CI of electricity from this study was 70.6 gCO2e/MJ, lower than the average electricity grid CI in California (82.92 gCO2e/MJ). The economic analysis results show that generating electricity alone can be profitable, while biodiesel produced via this system is not cost competitive with conventional diesel due to high capital expenses. Thus, generating electricity in lieu of biodiesel appears to be a better option to maximize the use of waste flows and supply lower-carbon energy.
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Affiliation(s)
- Jin Wook Ro
- Institute of Transportation Studies, University of California, Davis, Davis, CA, 95616, United States.
| | - Cody Yothers
- Dept. of Chemistry, University of California, Davis, Davis, CA, 95616, United States.
| | - Alissa Kendall
- Dept. of Civil and Environmental Engineering, University of California, Davis, Davis, CA, 95616, United States.
| | - Annaliese Franz
- Dept. of Chemistry, University of California, Davis, Davis, CA, 95616, United States.
| | - Ruihong Zhang
- Dept. of Biological and Agricultural Engineering, University of California, Davis, Davis, CA, 95616, United States.
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Liang W, Wei L, Wang Q, You W, Poetsch A, Du X, Lv N, Xu J. Knocking Out Chloroplastic Aldolases/Rubisco Lysine Methyltransferase Enhances Biomass Accumulation in Nannochloropsis oceanica under High-Light Stress. Int J Mol Sci 2024; 25:3756. [PMID: 38612566 PMCID: PMC11012178 DOI: 10.3390/ijms25073756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 03/10/2024] [Accepted: 03/12/2024] [Indexed: 04/14/2024] Open
Abstract
Rubisco large-subunit methyltransferase (LSMT), a SET-domain protein lysine methyltransferase, catalyzes the formation of trimethyl-lysine in the large subunit of Rubisco or in fructose-1,6-bisphosphate aldolases (FBAs). Rubisco and FBAs are both vital proteins involved in CO2 fixation in chloroplasts; however, the physiological effect of their trimethylation remains unknown. In Nannochloropsis oceanica, a homolog of LSMT (NoLSMT) is found. Phylogenetic analysis indicates that NoLSMT and other algae LSMTs are clustered in a basal position, suggesting that algal species are the origin of LSMT. As NoLSMT lacks the His-Ala/ProTrp triad, it is predicted to have FBAs as its substrate instead of Rubisco. The 18-20% reduced abundance of FBA methylation in NoLSMT-defective mutants further confirms this observation. Moreover, this gene (nolsmt) can be induced by low-CO2 conditions. Intriguingly, NoLSMT-knockout N. oceanica mutants exhibit a 9.7-13.8% increase in dry weight and enhanced growth, which is attributed to the alleviation of photoinhibition under high-light stress. This suggests that the elimination of FBA trimethylation facilitates carbon fixation under high-light stress conditions. These findings have implications in engineering carbon fixation to improve microalgae biomass production.
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Affiliation(s)
- Wensi Liang
- Single-Cell Center, CAS Key Laboratory of Biofuels, Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; (W.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Li Wei
- Single-Cell Center, CAS Key Laboratory of Biofuels, Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; (W.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qintao Wang
- Single-Cell Center, CAS Key Laboratory of Biofuels, Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; (W.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wuxin You
- Single-Cell Center, CAS Key Laboratory of Biofuels, Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; (W.L.)
| | - Ansgar Poetsch
- Single-Cell Center, CAS Key Laboratory of Biofuels, Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; (W.L.)
| | - Xuefeng Du
- Single-Cell Center, CAS Key Laboratory of Biofuels, Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; (W.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Nana Lv
- Single-Cell Center, CAS Key Laboratory of Biofuels, Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; (W.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jian Xu
- Single-Cell Center, CAS Key Laboratory of Biofuels, Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; (W.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
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Kadam RV, Rani V, Padmavathy P, Shalini R, Selvi MJT, Narsale SA. Assessment of heavy metals and environmental stress conditions on the production potential of polyunsaturated fatty acids (PUFAs) in indigenous microalgae isolated from the Gulf of Mannar coastal waters. ENVIRONMENTAL MONITORING AND ASSESSMENT 2024; 196:301. [PMID: 38400851 DOI: 10.1007/s10661-024-12447-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 02/12/2024] [Indexed: 02/26/2024]
Abstract
The present study evaluated the effects of heavy metals, viz., lead, mercury, and cadmium, on growth, chlorophyll a, b, c, carotenoids, and PUFA content of marine microalgae Chlorella sp. and Cylindrotheca fusiformis. At 96-h exposure, the IC50 values for Hg2+, Pb2+, and Cd2+ were 0.85 mg/L, 2.4 mg/L, and 5.3 mg/L respectively, in Chlorella sp. In C. fusiformis, IC50 values for Hg2+, Pb2+, and Cd2+ were 0.5 mg/L, 1.2 mg/L, and 3 mg/L respectively. The pigment contents of both microalgae were significantly affected upon heavy metal exposure. In Chlorella sp. and C. fusiformis, the exposed concentrations of Hg2+ averagely decreased the PUFA content by 76.34% and 78.68%, respectively. Similarly, Pb2+-exposed concentrations resulted in 54.50% and 82.64% average reductions in PUFA content of Chlorella sp. and C. fusiformis, respectively. Cd2+-exposed concentrations showed 32.58% and 40.54% average reduction in PUFA content of Chlorella sp. and C. fusiformis, respectively. Among the environmental stress conditions, the dark treatment has increased total PUFA content by 6.63% in Chlorella sp. and 3.92% in C. fusiformis. It was observed that the 50% nitrogen starvation (two-stage) significantly improved the PUFA production from 26.47 ± 6.55% to 40.92 ± 10.74% in Chlorella sp. and from 11.23 ± 5.01 to 32.8 ± 14.17% in C. fusiformis. The toxicity for both microalgae was followed in the order Hg2+ > Pb2+ > Cd2+. Among the two species, Chlorella sp. has shown a high tolerance to heavy metals and can be effectively utilized in PUFA production.
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Affiliation(s)
- Rishikesh Venkatrao Kadam
- Department of Aquatic Environment Management, Fisheries College and Research Institute, Tamil Nadu Dr. J. Jayalalithaa Fisheries University, Thoothukudi, 628 008, Tamil Nadu, India
| | - V Rani
- Department of Aquatic Environment Management, Fisheries College and Research Institute, Tamil Nadu Dr. J. Jayalalithaa Fisheries University, Thoothukudi, 628 008, Tamil Nadu, India.
| | - P Padmavathy
- Department of Aquatic Environment Management, Fisheries College and Research Institute, Tamil Nadu Dr. J. Jayalalithaa Fisheries University, Thoothukudi, 628 008, Tamil Nadu, India
| | - R Shalini
- Department of Fish Quality Assurance and Management, Fisheries College and Research Institute, Tamil Nadu Dr. J. Jayalalithaa Fisheries University, Thoothukudi, 628 008, Tamil Nadu, India
| | - M J Thamarai Selvi
- Department of Aquatic Environment Management, Fisheries College and Research Institute, Tamil Nadu Dr. J. Jayalalithaa Fisheries University, Thoothukudi, 628 008, Tamil Nadu, India
| | - Swapnil Ananda Narsale
- Department of Fish Pathology and Health Management, Fisheries College and Research Institute, Tamil Nadu Dr. J. Jayalalithaa Fisheries University, Thoothukudi, 628 008, Tamil Nadu, India
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Purba LDA, Susanti H, Admirasari R, Praharyawan S, Taufikurahman, Iwamoto K. Bibliometric insights into microalgae cultivation in wastewater: Trends and future prospects for biolipid production and environmental sustainability. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 352:120104. [PMID: 38242026 DOI: 10.1016/j.jenvman.2024.120104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 12/01/2023] [Accepted: 01/11/2024] [Indexed: 01/21/2024]
Abstract
Cultivation of microalgae in wastewater stream has been extensively reported, especially for simultaneous production of biolipid and wastewater treatment process. This study aimed to derive the research trend and focus on biolipid production from microalgae cultivated in wastewater by using bibliometric approach. The search strategy used in Scopus database resulted in 1339 research articles from 1990 to November 2023. Majority of publications (46%) were affiliated to China and India, showing their predominance in this field. Keywords related to the center of attention included biodiesel, biofuel, biomass and nutrient removal. Meanwhile, keyword with recent publication year, indicating the emerging research trends, revolved around the cultivation techniques and application of the system. Co-culture involving more than one microalgae species, bacteria and yeast showed promising results, while addition of nanoparticles was also found to be beneficial. Increasing exploration on the application of microalgae for treatment of saline wastewater was also reported and the carbon fixation mechanism by microalgae has been widely investigated to promote less environmental impact. Future research on these topics were suggested based on the findings of the bibliometric analyses.
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Affiliation(s)
- Laila Dina Amalia Purba
- Research Center for Applied Microbiology, National Research and Innovation Agency (BRIN), Cibinong, 16911, West Java, Indonesia.
| | - Hani Susanti
- Research Center for Applied Microbiology, National Research and Innovation Agency (BRIN), Cibinong, 16911, West Java, Indonesia
| | - Rahmania Admirasari
- Research Center for Applied Microbiology, National Research and Innovation Agency (BRIN), Cibinong, 16911, West Java, Indonesia
| | - Swastika Praharyawan
- Research Center for Applied Microbiology, National Research and Innovation Agency (BRIN), Cibinong, 16911, West Java, Indonesia
| | - Taufikurahman
- School of Life Science and Technology, Institut Teknologi Bandung, Jalan Ganesa No. 10, Bandung, 40132, Indonesia
| | - Koji Iwamoto
- Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur, 54100, Malaysia
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El-Sheekh MM, Galal HR, Mousa ASH, Farghl AAM. Impact of macronutrients and salinity stress on biomass and biochemical constituents in Monoraphidium braunii to enhance biodiesel production. Sci Rep 2024; 14:2725. [PMID: 38302601 DOI: 10.1038/s41598-024-53216-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 01/30/2024] [Indexed: 02/03/2024] Open
Abstract
Microalgal lipids are precursors to the production of biodiesel, as well as a source of valuable dietary components in the biotechnological industries. So, this study aimed to assess the effects of nutritional (nitrogen, and phosphorus) starvations and salinity stress (NaCl) on the biomass, lipid content, fatty acids profile, and predicted biodiesel properties of green microalga Monoraphidium braunii. The results showed that biomass, biomass productivity, and photosynthetic pigment contents (Chl. a, b, and carotenoids) of M. braunii were markedly decreased by nitrogen and phosphorus depletion and recorded the maximum values in cultures treated with full of N and P concentrations (control, 100%). These parameters were considerably increased at the low salinity level (up to 150 mM NaCl), while an increasing salinity level (up to 250 mM NaCl) reduces the biomass, its productivity, and pigment contents. Nutritional limitations and salt stress (NaCl) resulted in significantly enhanced accumulation of lipid and productivity of M. braunii, which represented more than twofold of the control. Furthermore, these conditions have enhanced the profile of fatty acid and biodiesel quality-related parameters. The current study exposed strategies to improve M. braunii lipid productivity for biodiesel production on a small scale in vitro in terms of fuel quality under low nutrients and salinity stress.
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Affiliation(s)
- Mostafa M El-Sheekh
- Botany Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt.
| | - Hamdy R Galal
- Botany and Microbiology Department, Faculty of Science, South Valley University, Qena, 83523, Egypt
| | - Amal Sh H Mousa
- Botany and Microbiology Department, Faculty of Science, South Valley University, Qena, 83523, Egypt
| | - Abla A M Farghl
- Botany and Microbiology Department, Faculty of Science, South Valley University, Qena, 83523, Egypt
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