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Dai JL, Song DX, Chen HH, Liang MH, Jiang JG. Effects of Piperonyl Butoxide on the Accumulation of Lipid and the Transcript Levels of DtMFPα in Dunaliella tertiolecta. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:12074-12084. [PMID: 36122177 DOI: 10.1021/acs.jafc.2c03006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
As one of the sources of biodiesel, microalgae are expected to solve petroleum shortage. In this study, different concentrations of piperonyl butoxide were added to the culture medium to investigate their effects on the growth, pigment content, lipid accumulation, and content of carotenoids in Dunaliella tertiolecta. The results showed that piperonyl butoxide addition significantly decreased the biomass, chlorophyll content, and total carotenoid content but hugely increased the lipid accumulation. With the treatment of 150 ppm piperonyl butoxide combined with 8000 Lux light intensity, the final lipid accumulation and single-cell lipid content were further increased by 21.79 and 76.42% compared to those of the control, respectively. The lipid accumulation in D. tertiolecta is probably related to the increased expression of DtMFPα in D. tertiolecta under the action of piperonyl butoxide. The phylogenetic trees of D. tertiolecta and other oil-rich plants were constructed by multiple sequence alignment of DtMFPα, demonstrating their evolutionary relationship, and the tertiary structure of DtMFPα was predicted. In conclusion, piperonyl butoxide has a significant effect on lipid accumulation in D. tertiolecta, which provides valuable insights into chemical inducers to enhance biodiesel production in microalgae to solve the problem of diesel shortage.
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Affiliation(s)
- Jv-Liang Dai
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - De-Xing Song
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Hao-Hong Chen
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Ming-Hua Liang
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Jian-Guo Jiang
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
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Shah AM, Mohamed H, Fazili ABA, Yang W, Song Y. Investigating the Effect of Alcohol Dehydrogenase Gene Knockout on Lipid Accumulation in Mucor circinelloides WJ11. J Fungi (Basel) 2022; 8:jof8090917. [PMID: 36135642 PMCID: PMC9503276 DOI: 10.3390/jof8090917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 08/22/2022] [Accepted: 08/25/2022] [Indexed: 11/16/2022] Open
Abstract
Mucor circinelloides is an oleaginous, dimorphic zygomycete fungus species that produces appreciable levels of ethanol when grown under aerobic conditions in the presence of high glucose, indicating the fungus is a Crabtree-positive microorganism. Engineering efforts to redirect carbon flux from ethanol to lipid biosynthesis may shed light on the critical role of ethanol biosynthesis during aerobic fermentation in M. circinelloides. Therefore, in this study, the alcohol dehydrogenase gene (ADH1) of M. circinelloides WJ11 was deleted, and its effects on growth, lipid production, and fatty acid content were analyzed. Our results showed that knocking out of adh1∆ reduced the ethanol concentration by 85–90% in fermented broth, indicating that this gene is the major source of ethanol production. Parallel to these findings, the lipid and fatty acid content of the mutant was decreased, while less change in the growth of WJ11 was observed. Furthermore, a fermentation study showed the lipid and fatty acid content was restored in the mutant strain when the fermentation media was supplemented with 0.5% external ethanol, indicating the importance of alcohol dehydrogenase and its product on growth and lipid biosynthesis in M. circinelloides. To our knowledge, this is the first study to show a link between alcohol dehydrogenase and lipid production in M. circinelloides.
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Affiliation(s)
- Aabid Manzoor Shah
- Colin Ratledge Center of Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Hassan Mohamed
- Colin Ratledge Center of Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assiut 71524, Egypt
| | - Abu Bakr Ahmad Fazili
- Colin Ratledge Center of Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Wu Yang
- Colin Ratledge Center of Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Yuanda Song
- Colin Ratledge Center of Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
- Correspondence:
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Accumulation of medium chain fatty acids in Nannochloropsis oceanica by heterologous expression of Cuphea palustris thioesterase FatB1. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Joshi A, Verma KK, D Rajput V, Minkina T, Arora J. Recent advances in metabolic engineering of microorganisms for advancing lignocellulose-derived biofuels. Bioengineered 2022; 13:8135-8163. [PMID: 35297313 PMCID: PMC9161965 DOI: 10.1080/21655979.2022.2051856] [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] [Indexed: 01/09/2023] Open
Abstract
Combating climate change and ensuring energy supply to a rapidly growing global population has highlighted the need to replace petroleum fuels with clean, and sustainable renewable fuels. Biofuels offer a solution to safeguard energy security with reduced ecological footprint and process economics. Over the past years, lignocellulosic biomass has become the most preferred raw material for the production of biofuels, such as fuel, alcohol, biodiesel, and biohydrogen. However, the cost-effective conversion of lignocellulose into biofuels remains an unsolved challenge at the industrial scale. Recently, intensive efforts have been made in lignocellulose feedstock and microbial engineering to address this problem. By improving the biological pathways leading to the polysaccharide, lignin, and lipid biosynthesis, limited success has been achieved, and still needs to improve sustainable biofuel production. Impressive success is being achieved by the retouring metabolic pathways of different microbial hosts. Several robust phenotypes, mostly from bacteria and yeast domains, have been successfully constructed with improved substrate spectrum, product yield and sturdiness against hydrolysate toxins. Cyanobacteria is also being explored for metabolic advancement in recent years, however, it also remained underdeveloped to generate commercialized biofuels. The bacterium Escherichia coli and yeast Saccharomyces cerevisiae strains are also being engineered to have cell surfaces displaying hydrolytic enzymes, which holds much promise for near-term scale-up and biorefinery use. Looking forward, future advances to achieve economically feasible production of lignocellulosic-based biofuels with special focus on designing more efficient metabolic pathways coupled with screening, and engineering of novel enzymes.
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Affiliation(s)
- Abhishek Joshi
- Laboratory of Biomolecular Technology, Department of Botany, Mohanlal Sukhadia University, Udaipur313001, India
| | - Krishan K. Verma
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs/Guangxi Key Laboratory of Sugarcane Genetic improvement/Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning - 530007, China
| | - Vishnu D Rajput
- Academy of Biology and Biotechnology, Southern Federal University, 344090, Russia
| | - Tatiana Minkina
- Academy of Biology and Biotechnology, Southern Federal University, 344090, Russia
| | - Jaya Arora
- Laboratory of Biomolecular Technology, Department of Botany, Mohanlal Sukhadia University, Udaipur313001, India,CONTACT Jaya Arora Laboratory of Biomolecular Technology, Department of Botany, Mohanlal Sukhadia University, Udaipur313001, India
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Fazili ABA, Shah AM, Zan X, Naz T, Nosheen S, Nazir Y, Ullah S, Zhang H, Song Y. Mucor circinelloides: a model organism for oleaginous fungi and its potential applications in bioactive lipid production. Microb Cell Fact 2022; 21:29. [PMID: 35227264 PMCID: PMC8883733 DOI: 10.1186/s12934-022-01758-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/10/2022] [Indexed: 11/10/2022] Open
Abstract
Microbial oils have gained massive attention because of their significant role in industrial applications. Currently plants and animals are the chief sources of medically and nutritionally important fatty acids. However, the ever-increasing global demand for polyunsaturated fatty acids (PUFAs) cannot be met by the existing sources. Therefore microbes, especially fungi, represent an important alternative source of microbial oils being investigated. Mucor circinelloides—an oleaginous filamentous fungus, came to the forefront because of its high efficiency in synthesizing and accumulating lipids, like γ-linolenic acid (GLA) in high quantity. Recently, mycelium of M. circinelloides has acquired substantial attraction towards it as it has been suggested as a convenient raw material source for the generation of biodiesel via lipid transformation. Although M. circinelloides accumulates lipids naturally, metabolic engineering is found to be important for substantial increase in their yields. Both modifications of existing pathways and re-formation of biosynthetic pathways in M. circinelloides have shown the potential to improve lipid levels. In this review, recent advances in various important metabolic aspects of M. circinelloides have been discussed. Furthermore, the potential applications of M. circinelloides in the fields of antioxidants, nutraceuticals, bioremediation, ethanol production, and carotenoids like beta carotene and astaxanthin having significant nutritional value are also deliberated.
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Balkrishna A, Rastogi S, Kharayat B, Tomer M, Varshney Y, Singh K, Kumari P, Dev R, Srivastava J, Haldar S, Varshney A. Anu taila, an herbal nasal-drop, suppresses mucormycosis by regulating host TNF-α response and fungal ergosterol biosynthesis. J Appl Microbiol 2022; 132:3355-3374. [PMID: 35025137 DOI: 10.1111/jam.15451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 01/01/2022] [Accepted: 01/10/2022] [Indexed: 11/27/2022]
Abstract
AIM The intractable, mucormycosis, caused by Mucorales primarily targets immunocompromised individuals. The first-line therapy, intravenous liposomal Amphotericin B and surgical debridement of necrotic tissue, is contraindicative in individuals with compromised kidneys. This invokes a pressing need to identify safer treatment options. METHODS AND RESULTS Antifungal effect of the classical nasal drop, Anu taila, against Mucor spp. was investigated through microbiological, cytological, analytical chemical (HPLC and GS/MS/MS) and field emission scanning electron microscopic (FE-SEM) approaches. Anu taila pre-treated spores germinated late, resulting in reduced infectivity, observed as milder monocytic immune response. Conversely, Anu taila pre-treated THP-1 cells exhibited an improved immune response, through TNF-α, against Mucor spores. Repeated Anu taila application abolished fungal microarchitectures faster than Amphotericin B, evident from rapid replacement of hyphae, sporangiophores and sporangia with fused biomass, in the FESEM images. Anu taila downregulated sterol-C5-desaturase-coding ERG3 gene, crucial for ergosterol biosynthesis and resultant structural integrity, in Mucor spp. CONCLUSION Taken together, Anu taila was found effective against Mucor spp., with both prophylactic and curative implications, attributable to its phytochemical composition. SIGNIFICANCE Potential remedial effects of a classical nasal drop against an obdurate and challenging fungal infection are identified.
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Affiliation(s)
- Acharya Balkrishna
- Drug Discovery and Development Division, Patanjali Research Institute, Haridwar, Uttarakhand, India.,Department of Allied and Applied Sciences, University of Patanjali, Haridwar, Uttarakhand, India
| | - Shubhangi Rastogi
- Department of Microbiology, Patanjali Research Institute, Haridwar, Uttarakhand, India
| | - Bhawana Kharayat
- Department of Microbiology, Patanjali Research Institute, Haridwar, Uttarakhand, India
| | - Meenu Tomer
- Department of Chemistry, Patanjali Research Institute, Haridwar, Uttarakhand, India
| | - Yash Varshney
- Department of Chemistry, Patanjali Research Institute, Haridwar, Uttarakhand, India
| | - Kanchan Singh
- Department of Microbiology, Patanjali Research Institute, Haridwar, Uttarakhand, India
| | - Priya Kumari
- Department of Biology, Patanjali Research Institute, Haridwar, Uttarakhand, India
| | - Rishabh Dev
- Department of Biology, Patanjali Research Institute, Haridwar, Uttarakhand, India
| | - Jyotish Srivastava
- Department of Chemistry, Patanjali Research Institute, Haridwar, Uttarakhand, India
| | - Swati Haldar
- Drug Discovery and Development Division, Patanjali Research Institute, Haridwar, Uttarakhand, India.,Department of Microbiology, Patanjali Research Institute, Haridwar, Uttarakhand, India
| | - Anurag Varshney
- Drug Discovery and Development Division, Patanjali Research Institute, Haridwar, Uttarakhand, India.,Department of Allied and Applied Sciences, University of Patanjali, Haridwar, Uttarakhand, India.,Special Centre for Systems Medicine, Jawaharlal Nehru University, New Delhi, India
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Wu Q, Jiang Y, Chen Y, Liu M, Bao X, Guo W. Opportunities and challenges in microbial medium chain fatty acids production from waste biomass. BIORESOURCE TECHNOLOGY 2021; 340:125633. [PMID: 34315125 DOI: 10.1016/j.biortech.2021.125633] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/16/2021] [Accepted: 07/17/2021] [Indexed: 06/13/2023]
Abstract
Medium chain fatty acids (MCFAs) that produced from affordable waste biomass via chain elongation (CE) technology are recognized as the potential alternatives to part fossil-derived chemicals, contributing to the sustainable development of economy and environment. The purpose of this review is to provide comprehensive analyses on the opportunities and challenges of MCFAs production and application. First, both two microbial MCFAs synthesis pathways of reverse β-oxidation and fatty acid biosynthesis were introduced/compared in detail to give readers a thorough understanding of the CE process, with the expectation of further boosting MCFAs production by well distinguishing them. Furthermore, the six key MCFAs production bottlenecks, corresponding research progresses, and possible solutions were analyzed. Five major MCFAs production strategies with their production mechanism, performances, and characteristics were also critically assessed. Additionally, the commercial production status was introduced, and future alternative production mode and research priorities were also recommended.
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Affiliation(s)
- Qinglian Wu
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Yong Jiang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Ying Chen
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Min Liu
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Xian Bao
- School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| | - Wanqian Guo
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
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Deep learning strategies for active secondary metabolites biosynthesis from fungi: Harnessing artificial manipulation and application. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2021.102195] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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9
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Hussain SA, Sarker MI, Yosief HO, Yadav MP. Evaluation of diverse biochemical stimulants to enhance growth, lipid and docosahexaenoic acid (DHA) production of Aurantiochytrium Sp. ATCC PRA-276. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2021.102122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Mass spore production of Mucor circinelloides on rice. 3 Biotech 2021; 11:311. [PMID: 34109096 DOI: 10.1007/s13205-021-02853-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 05/19/2021] [Indexed: 10/21/2022] Open
Abstract
Mucor circinelloides is a fungus that produces diverse spores throughout its life cycle. The sporangiospores, which are the most well-studied spores in this fungus, are asexual spores produced during aerial mycelial development. M. circinelloides has the potential to be used in diverse biotechnological applications. In this study, we propose rice (Oryza sativa) grains as an alternative substrate for inexpensive and large-scale sporangiospore production. The sporangiospores produced from rice and a yeast extract-peptone-glucose (YPG) medium exhibited similar protein and nucleic acid contents and phenotypes in terms of germination under different conditions and culture media, including similar virulence rates against the nematode Caenorhabditis elegans. Transgenic strains carrying self-replicative plasmids were sporulated on rice and showed plasmid stability similar to that of spores produced on the YPG medium. Approximately 20% of the spore population lost plasmids after the first passage on rice. These results reveal that rice is a suitable substrate for the mass production of sporangiospores in M. circinelloides. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s13205-021-02853-1.
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Enhanced lipid production by addition of malic acid in fermentation of recombinant Mucor circinelloides Mc-MT-2. Sci Rep 2021; 11:12674. [PMID: 34135458 PMCID: PMC8208983 DOI: 10.1038/s41598-021-92324-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 06/02/2021] [Indexed: 11/29/2022] Open
Abstract
In our previous work, we reported a novel approach for increasing lipid production in an oleaginous fungus Mucor circinelloides by overexpression of mitochondrial malate transporter protein. This transporter plays a vital role in fatty acid biosynthesis during malate and citrate transport systems in oleaginous fungi. In this study, the controlling metabolic supplementation strategy was used to improve the lipid production by overexpression of malate transporter protein in M. circinelloides strain coded as Mc-MT-2. The effects of different metabolic intermediates on lipid production in batch fermentation by Mc-MT-2 were investigated. The optimal lipid production was obtained at 0.8% malic acid after 24 h of fermentation. Furthermore, in fed-batch bioreactors containing glucose as a carbon source supplemented with malic acid, the highest cell growth, and lipid production were achieved. The resulting strain showed the fungal dry biomass of 16 g/L, a lipid content of 32%, lipid yield of 5.12 g/L in a controlled bench-top bioreactor, with 1.60-, 1.60- and 2.56-fold improvement, respectively, compared with the batch control without supplementation of malic acid. Our findings revealed that the addition of malic acid during fermentation might play an important role in lipid accumulation in the recombinant M. circinelloides Mc-MT-2. This study provides valuable insights for enhanced microbial lipid production through metabolic supplementation strategy in large scale and industrial applications.
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Role of Snf-β in lipid accumulation in the high lipid-producing fungus Mucor circinelloides WJ11. Microb Cell Fact 2021; 20:52. [PMID: 33639948 PMCID: PMC7916304 DOI: 10.1186/s12934-021-01545-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 02/18/2021] [Indexed: 12/23/2022] Open
Abstract
Background Mucor circinelloides WJ11 is a high-lipid producing strain and an excellent producer of γ-linolenic acid (GLA) which is crucial for human health. We have previously identified genes that encode for AMP-activated protein kinase (AMPK) complex in M. circinelloides which is an important regulator for lipid accumulation. Comparative transcriptional analysis between the high and low lipid-producing strains of M. circinelloides showed a direct correlation in the transcriptional level of AMPK genes with lipid metabolism. Thus, the role of Snf-β, which encodes for β subunit of AMPK complex, in lipid accumulation of the WJ11 strain was evaluated in the present study. Results The results showed that lipid content of cell dry weight in Snf-β knockout strain was increased by 32 % (from 19 to 25 %). However, in Snf-β overexpressing strain, lipid content of cell dry weight was decreased about 25 % (from 19 to 14.2 %) compared to the control strain. Total fatty acid analysis revealed that the expression of the Snf-β gene did not significantly affect the fatty acid composition of the strains. However, GLA content in biomass was increased from 2.5 % in control strain to 3.3 % in Snf-β knockout strain due to increased lipid accumulation and decreased to 1.83 % in Snf-β overexpressing strain. AMPK is known to inactivate acetyl-CoA carboxylase (ACC) which catalyzes the rate-limiting step in lipid synthesis. Snf-β manipulation also altered the expression level of the ACC1 gene which may indicate that Snf-β control lipid metabolism by regulating ACC1 gene. Conclusions Our results suggested that Snf-β gene plays an important role in regulating lipid accumulation in M. circinelloides WJ11. Moreover, it will be interesting to evaluate the potential of other key subunits of AMPK related to lipid metabolism. Better insight can show us the way to manipulate these subunits effectively for upscaling the lipid production. Up to our knowledge, it is the first study to investigate the role of Snf-β in lipid accumulation in M. circinelloides.
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Mhlongo SI, Ezeokoli OT, Roopnarain A, Ndaba B, Sekoai PT, Habimana O, Pohl CH. The Potential of Single-Cell Oils Derived From Filamentous Fungi as Alternative Feedstock Sources for Biodiesel Production. Front Microbiol 2021; 12:637381. [PMID: 33584636 PMCID: PMC7876240 DOI: 10.3389/fmicb.2021.637381] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 01/07/2021] [Indexed: 11/13/2022] Open
Abstract
Microbial lipids, also known as single-cell oils (SCOs), are highly attractive feedstocks for biodiesel production due to their fast production rates, minimal labor requirements, independence from seasonal and climatic changes, and ease of scale-up for industrial processing. Among the SCO producers, the less explored filamentous fungi (molds) exhibit desirable features such as a repertoire of hydrolyzing enzymes and a unique pellet morphology that facilitates downstream harvesting. Although several oleaginous filamentous fungi have been identified and explored for SCO production, high production costs and technical difficulties still make the process less attractive compared to conventional lipid sources for biodiesel production. This review aims to highlight the ability of filamentous fungi to hydrolyze various organic wastes for SCO production and explore current strategies to enhance the efficiency and cost-effectiveness of the SCO production and recovery process. The review also highlights the mechanisms and components governing lipogenic pathways, which can inform the rational designs of processing conditions and metabolic engineering efforts for increasing the quality and accumulation of lipids in filamentous fungi. Furthermore, we describe other process integration strategies such as the co-production with hydrogen using advanced fermentation processes as a step toward a biorefinery process. These innovative approaches allow for integrating upstream and downstream processing units, thus resulting in an efficient and cost-effective method of simultaneous SCO production and utilization for biodiesel production.
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Affiliation(s)
- Sizwe I. Mhlongo
- Discipline of Medical Microbiology, School of Laboratory Medicine and Medical Sciences, Medical School, University of KwaZulu-Natal, Durban, South Africa
| | - Obinna T. Ezeokoli
- Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, Bloemfontein, South Africa
| | - Ashira Roopnarain
- Microbiology and Environmental Biotechnology Research Group, Institute for Soil, Climate and Water, Agricultural Research Council, Pretoria, South Africa
| | - Busiswa Ndaba
- Microbiology and Environmental Biotechnology Research Group, Institute for Soil, Climate and Water, Agricultural Research Council, Pretoria, South Africa
| | - Patrick T. Sekoai
- The School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong
| | - Olivier Habimana
- The School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong
| | - Carolina H. Pohl
- Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, Bloemfontein, South Africa
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