Consortium Growth of Filamentous Fungi and Microalgae: Evaluation of Different Cultivation Strategies to Optimize Cell Harvesting and Lipid Accumulation

This study aims to evaluate the potential of consortium biomass formation between Mucor circinelloides, an oleaginous filamentous fungal species, and Chlorella vulgaris, in order to promote a straightforward approach to harvest microalgal cells and to evaluate the lipid production in the consortium system. A synthetic medium with glucose (2 g·L−1) and mineral nutrients essential for both fungi and algae was selected. Four different inoculation strategies were assessed, considering the effect of simultaneous vs. separate development of fungal spores and algae cells, and the presence of a supporting matrix aiming at the higher recovery of algae cell rates. The results were evaluated in terms of consortium biomass composition, demonstrating that the strategy using a mature fungal mycelium with a higher algae count may provide biomass samples with up to 79% of their dry weight as algae, still promoting recovery rates greater than 97%. The findings demonstrate a synergistic effect on the lipid accumulation by the fungal strain, at around a fourfold increase when compared to the axenic control, with values in the range of 23% of dry biomass weight. Furthermore, the fatty acid profile from the samples presents a balance between saturated and unsaturated fatty acids that is likely to present an adequate balance for applications such as biodiesel production.

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Genome-scale metabolic modelling underscores the potential of Cutaneotrichosporon oleaginosus ATCC 20509 as a cell factory for biofuel production

10.21203/rs.3.rs-26414/v1 ◽

2020 ◽

Author(s):

Nhung TT Pham ◽

Maarten Reijnders ◽

Maria Suarez-Diez ◽

Bart Nijsse ◽

Jan Springer ◽

...

Keyword(s):

Carbon Source ◽

Lipid Accumulation ◽

Crude Glycerol ◽

Unsaturated Fatty Acids ◽

Biodiesel Production ◽

Biofuel Production ◽

Cell Factory ◽

A Genome ◽

Wide Range ◽

Genome Scale

Abstract Background: Cutaneotrichosporon oleaginosus ATCC 20509 is a fast growing oleaginous basidiomycete yeast that is able to grow in a wide range of low-cost carbon sources including crude glycerol, a byproduct of biodiesel production. When glycerol is used as a carbon source, this yeast can accumulate more than 50% lipids (w/w) with high concentrations of mono-unsaturated fatty acids. Results: To increase our understanding of this yeast and to provide a knowledge base for further industrial use, a FAIR re-annotated genome was used to build a genome-scale, constraint-based metabolic model containing 1553 reactions involving 1373 metabolites in 11 compartments. A new description of the biomass synthesis reaction was introduced to account for massive lipid accumulation in conditions with high carbon to nitrogen (C/N) ratio in the media. This condition-speciﬁc biomass objective function is shown to better predict conditions with high lipid accumulation using glucose, fructose, sucrose, xylose, ethanol and glycerol as sole carbon source. Conclusion: Contributing to the economic viability of biodiesel as renewable fuel, C. oleaginosus ATCC 20509 can eﬀectively convert crude glycerol waste streams in lipids as a potential bioenergy source. Performance simulations are essential to identify optimal production conditions and to develop and ﬁne tune a cost-eﬀective production process. Our model suggests ATP-citrate lyase as a target for overexpression to further improve lipid production.

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Genome-scale metabolic modelling underscores the potential of Cutaneotrichosporon oleaginosus ATCC 20509 as a cell factory for biofuel production

10.21203/rs.3.rs-26414/v3 ◽

2020 ◽

Author(s):

Nhung TT Pham ◽

Maarten Reijnders ◽

Maria Suarez-Diez ◽

Bart Nijsse ◽

Jan Springer ◽

...

Keyword(s):

Lipid Accumulation ◽

Crude Glycerol ◽

Lipid Production ◽

Biodiesel Production ◽

Biofuel Production ◽

Cell Factory ◽

Atp Citrate Lyase ◽

A Genome ◽

Wide Range ◽

Genome Scale

Abstract Background: Cutaneotrichosporon oleaginosus ATCC 20509 is a fast growing oleaginous basidiomycete yeast that is able to grow in a wide range of low-cost carbon sources including crude glycerol, a byproduct of biodiesel production. When glycerol is used as a carbon source, this yeast can accumulate more than 50% lipids (w/w) with high concentrations of mono-unsaturated fatty acids.Results: To increase our understanding of this yeast and to provide a knowledge base for further industrial use, a FAIR re-annotated genome was used to build a genome-scale, constraint-based metabolic model containing 1553 reactions involving 1373 metabolites in 11 compartments. A new description of the biomass synthesis reaction was introduced to account for massive lipid accumulation in conditions with high carbon to nitrogen (C/N) ratio in the media. This condition-specific biomass objective function is shown to better predict conditions with high lipid accumulation using glucose, fructose, sucrose, xylose, and glycerol as sole carbon source.Conclusion: Contributing to the economic viability of biodiesel as renewable fuel, C. oleaginosus ATCC 20509 can effectively convert crude glycerol waste streams in lipids as a potential bioenergy source. Performance simulations are essential to identify optimal production conditions and to develop and fine tune a cost-effective production process. Our model suggests ATP-citrate lyase as a possible target to further improve lipid production.

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Overexpression of an Inulinase Gene in an Oleaginous Yeast, Aureobasidium melanogenum P10, for Efficient Lipid Production from Inulin

Journal of Molecular Microbiology and Biotechnology ◽

10.1159/000493139 ◽

2018 ◽

Vol 28 (4) ◽

pp. 190-200 ◽

Cited By ~ 1

Author(s):

Yan-Feng Li ◽

Hong Jiang ◽

Zhong Hu ◽

Guang-Lei Liu ◽

Zhen-Ming Chi ◽

...

Keyword(s):

Lipid Production ◽

Dry Weight ◽

Genetically Engineered ◽

Biodiesel Production ◽

Yeast Cells ◽

Gene Encoding ◽

Direct Production ◽

Inulinase Gene ◽

Inulinase Activity ◽

Engineered Yeast

In this study, in order to directly and efficiently convert inulin into a single-cell oil (SCO), an INU1 gene encoding inulinase from Kluyveromyces marxianus was integrated into the genomic DNA and actively expressed in an SCO producer Aureobasidium melanogenum P10. The transformant API41 obtained produced 28.5 U/mL of inulinase and its wild-type strain P10 yielded only 8.62 U/mL. Most (97.5%) of the inulinase produced by the transformant API41 was secreted into the culture. During a 10-L fermentation, 66.2% (w/w) lipid in the yeast cells of the transformant API41 and 14.38 g/L of cell dry weight were attained from inulin of 80.0 g/L within 120 h, high inulinase activity (23.7 U/mL) was also produced within 72 h, and the added inulin was actively hydrolyzed. This confirmed that the genetically engineered yeast of A. melanogenum P10 is suitable for direct production of lipids from inulin. The lipids produced could be used as feedstocks for biodiesel production.

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Molecular Mechanism of Lipid Accumulation and Metabolism of Oleaginous Chlorococcum sphacosum GD from Soil under Salt Stress

International Journal of Molecular Sciences ◽

10.3390/ijms22031304 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1304

Author(s):

Hang Su ◽

Jia Feng ◽

Junping Lv ◽

Qi Liu ◽

Fangru Nan ◽

...

Keyword(s):

Salt Stress ◽

Fatty Acid ◽

Lipid Content ◽

Salt Concentration ◽

Lipid Accumulation ◽

Transcriptome Sequencing ◽

High Throughput Sequencing ◽

Lipid Production ◽

Biodiesel Production ◽

Oleaginous Microalgae

The oleaginous microalgae species Chlorococcum sphacosum GD is a promising feedstock for biodiesel production from soil. However, its metabolic mechanism of lipid production remains unclear. In this study, the lipid accumulation and metabolism mechanisms of Chlorococcum sphacosum GD were analyzed under salt stress based on transcriptome sequencing. The biomass and lipid content of the alga strain were determined under different NaCl concentrations, and total RNA from fresh cells were isolated and sequenced by HiSeq 2000 high throughput sequencing technology. As the salt concentration increased in culture medium, the algal lipid content increased but the biomass decreased. Following transcriptome sequencing by assembly and splicing, 24,128 unigenes were annotated, with read lengths mostly distributed in the 200–300 bp interval. Statistically significant differentially expressed unigenes were observed in different experimental groups, with 2051 up-regulated genes and 1835 down-regulated genes. The lipid metabolism pathway analysis showed that, under salt stress, gene-related fatty acid biosynthesis (ACCase, KASII, KAR, HAD, FATA) was significantly up-regulated, but some gene-related fatty acid degradation was significantly down-regulated. The comprehensive results showed that salt concentration can affect the lipid accumulation and metabolism of C. sphacosum GD, and the lipid accumulation is closely related to the fatty acid synthesis pathway.

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Two-Stage Cultivation of Dunaliella tertiolecta with Glycerol and Triethylamine for Lipid Accumulation: a Viable Way To Alleviate the Inhibitory Effect of Triethylamine on Biomass

Applied and Environmental Microbiology ◽

10.1128/aem.02614-18 ◽

2018 ◽

Vol 85 (4) ◽

Cited By ~ 1

Author(s):

Ming-Hua Liang ◽

Lu-Lu Xue ◽

Jian-Guo Jiang

Keyword(s):

Lipid Accumulation ◽

Lipid Production ◽

Algal Growth ◽

Inhibitory Effect ◽

Dunaliella Tertiolecta ◽

Biodiesel Production ◽

Two Stage ◽

Content Type ◽

Second Stage ◽

Cell Biomass

ABSTRACT Microalgae are promising alternatives for sustainable biodiesel production. Previously, it was found that 100 ppm triethylamine greatly enhanced lipid production and lipid content per cell of Dunaliella tertiolecta by 20% and 80%, respectively. However, triethylamine notably reduced biomass production and pigment contents. In this study, a two-stage cultivation with glycerol and triethylamine was attempted to improve cell biomass and lipid accumulation. At the first stage with 1.0 g/liter glycerol addition, D. tertiolecta cells reached the late log phase in a shorter time due to rapid cell growth, leading to the highest cell biomass (1.296 g/liter) for 16 days. However, the increased glycerol concentrations with glycerol addition decreased the lipid content. At the second-stage cultivation with 100 ppm triethylamine, the highest lipid concentration and lipid weight content were 383.60 mg/liter and 37.7% of dry cell weight (DCW), respectively, in the presence of 1.0 g/liter glycerol, which were 27.36% and 72.51% higher than those of the control group, respectively. Besides, the addition of glycerol alleviated the inhibitory effect of triethylamine on cell morphology, algal growth, and pigment accumulation in D. tertiolecta. The results indicated that two-stage cultivation is a viable way to improve lipid yield in microalgae. IMPORTANCE Microalgae are promising alternatives for sustainable biodiesel production. Two-stage cultivation with glycerol and triethylamine enhanced the lipid productivity of Dunaliella tertiolecta, indicating that two-stage cultivation is an efficient strategy for biodiesel production from microalgae. It was found that glycerol significantly enhanced cell biomass of D. tertiolecta, and the presence of glycerol alleviated the inhibitory effect of triethylamine on algal growth. Glycerol, the major byproduct from biodiesel production, was used for the biomass accumulation of D. tertiolecta at the first stage of cultivation. Triethylamine, as a lipid inducer, was used for lipid accumulation at the second stage of cultivation. Two-stage cultivation with glycerol and triethylamine enhanced lipid productivity and alleviated the inhibitory effect of triethylamine on the algal growth of D. tertiolecta, which is an efficient strategy for lipid production from D. tertiolecta.

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Production of chitosan and lipids from a newly isolated Mucor circinelloides

10.51415/10321/3183 ◽

2018 ◽

Author(s):

◽

Johnson Tungamirai Zininga

Keyword(s):

Sunflower Oil ◽

Unsaturated Fatty Acids ◽

Lipid Production ◽

Cetane Number ◽

Antimicrobial Properties ◽

Mucor Circinelloides ◽

Acid Number ◽

Biodiesel Production ◽

Oleaginous Fungi ◽

Enhanced Production

Filamentous fungi are well-known sources of a wide variety of industrially-useful biomolecules. This study demonstrates the applicability of a newly isolated oleaginous fungi Mucor circinelloides ZSKP for lipid and chitosan production. Parameters affecting co-production were identified and were statistically optimized, which resulted in a 3–fold improvement in lipid production. The lipid profile showed a high content of unsaturated fatty acids including oleic, linolenic and linoleic acids, while palmitic acid was the major saturated fatty acid (21%). A comparative study to evaluate the efficacy of enzymatic and chemical treatments for biodiesel production from fungal lipids and sunflower oil revealed slightly enhanced production of biodiesel from fungal lipids, using a commercial lipase. The biodiesel synthesized using lipids from M. circinelloides ZSKP satisfied standard specifications and had a higher cetane number (56), lower kinematic viscosity (4.6 mm2/s) and lower acid number (0.03) compared to sunflower oil. Upon optimizing chitosan production and extraction processes the chitosan production was improved 2-fold. The fungal chitosan showed antimicrobial properties and was more effective against Aspergillus niger A chitosan spray was developed which was able to increase the shelf life of fresh fruit produce. These results indicate that Mucor circinelloides ZSKP is a promising candidate for concurrent production of lipids and the versatile bio-polymer chitosan.

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Effect of Phytohormones Supplementation under Nitrogen Depletion on Biomass and Lipid Production of Nannochloropsis oceanica for Integrated Application in Nutrition and Biodiesel

Sustainability ◽

10.3390/su13020592 ◽

2021 ◽

Vol 13 (2) ◽

pp. 592

Author(s):

Hussein El-Sayed Touliabah ◽

Adel W. Almutairi

Keyword(s):

Fatty Acids ◽

Lipid Accumulation ◽

Saturated Fatty Acids ◽

Lipid Production ◽

Human Nutrition ◽

Biodiesel Production ◽

Nannochloropsis Oceanica ◽

Nitrogen Depletion ◽

Omega Fatty Acids ◽

Microalgal Lipids

Economic viability of biodiesel production relies mainly on the productivity of biomass and microalgal lipids. In addition, production of omega fatty acids is favorable for human nutrition. Thus, enhancement of lipid accumulation with high proportion of omega fatty acids could help the dual use of microalgal lipids in human nutrition and biodiesel production through biorefinery. In that context, phytohormones have been identified as a promising factor to increase biomass and lipids production. However, nitrogen limitation has been discussed as a potential tool for lipid accumulation in microalgae, which results in simultaneous growth retardation. The present study aims to investigate the combined effect of N-depletion and 3-Indoleacetic acid (IAA) supplementation on lipid accumulation of the marine eustigmatophyte Nannochloropsis oceanica as one of the promising microalgae for omega fatty acids production. The study confirmed that N-starvation stimulates the lipid content of N. oceanica. IAA enhanced both growth and lipid accumulation due to enhancement of pigments biosynthesis. Therefore, combination effect of IAA and nitrogen depletion showed gradual increase in the dry weight compared to the control. Lipid analysis showed lower quantity of saturated fatty acids (SFA, 26.25%) than the sum of monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA). Under N-depletion, SFA decreased by 12.98% compared to the control, which recorded much reduction by increasing of IAA concentration. Reduction of SFA was in favor of PUFA, mainly omega-6 and omega-3 fatty acids which increased significantly due to IAA combined with N-depletion. Thus, the present study suggests a biorefinery approach for lipids extracted from N. oceanica for dual application in nutrition followed by biodiesel production.

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The Effect of Trophic Modes on Biomass and Lipid Production of Five Microalgal Strains

Water ◽

10.3390/w14020240 ◽

2022 ◽

Vol 14 (2) ◽

pp. 240

Author(s):

Andonia Nicodemou ◽

Michalis Kallis ◽

Anastasia Agapiou ◽

Androulla Markidou ◽

Michalis Koutinas

Keyword(s):

Fatty Acids ◽

Unsaturated Fatty Acids ◽

Lipid Production ◽

Scenedesmus Obliquus ◽

Isochrysis Galbana ◽

Biomass Productivity ◽

Glucose Consumption ◽

Dry Weight ◽

Heterotrophic Cultivation ◽

High Lipid

Five microalgae strains, namely Isochrysis galbana, Microchloropsis gaditana, Scenedesmus obliquus, Nannochloropsis oculata and Tetraselmis suecica, were selected as potential candidates for polyunsaturated fatty acids’ production, evaluating biomass productivity and their capacity to accumulate high lipid contents under different trophic modes. Microalgae strains were cultivated in the presence of 1% glucose using mixotrophic and heterotrophic conditions, while autotrophic cultures served as control experiments. The results demonstrate that S. obliquus performed the highest biomass productivity that reached 0.13 and 0.14 g L−1 d−1 under mixotrophic and heterotrophic conditions, respectively. I. galbana and S. obliquus utilized elevated contents of glucose in mixotrophy, removing 55.9% and 95.6% of the initial concentration of the carbohydrate, respectively, while glucose consumption by the aforementioned strains also remained high under heterotrophic cultivation. The production of lipids was maximal for I. galbana in mixotrophy and S. obliquus in heterotrophy, performing lipid productivities of 24.85 and 22.77 mg L−1 d−1, respectively. The most abundant saturated acid detected for all microalgae strains evaluated was palmitic acid (C16:0), while oleic and linolenic acids (C18:1n9c/C18:3n3) comprised the most abundant unsaturated fatty acids. I. galbana performed the highest linoleic acid (C18:2n6c) content under heterotrophic nutrition, which reached 87.9 mg g−1 of ash-free dry weight. Among the microalgae strains compared, the biomass and lipid production monitored for I. galbana and S. obliquus confirm that both strains could serve as efficient bioproducers for application in algal biorefineries.

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Transcriptional profiling reveals differentially expressed genes involved in lipid biosynthesis during cacao seed development

Scientific Reports ◽

10.1038/s41598-019-53959-9 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Fupeng Li ◽

Baoduo Wu ◽

Lin Yan ◽

Chaoyun Hao ◽

Xiaowei Qin ◽

...

Keyword(s):

Differentially Expressed Genes ◽

Lipid Content ◽

Lipid Accumulation ◽

Unsaturated Fatty Acids ◽

Transcriptional Profiling ◽

Lipid Production ◽

Economic Value ◽

Lipid Synthesis ◽

Differentially Expressed ◽

Seed Lipid

AbstractTheobroma cacao is a plant of economic value due to the use of its seed lipid for chocolate, confectionery, and cosmetic industries. The seed lipid contains a stable ratio of saturated and unsaturated fatty acids, which determines its unique melting temperature. However, little is known about the molecular mechanism determining the fatty acid ratio and lipid content in cacao. To gain insight into the unique properties of lipid synthesis in cacao, biochemical and transcriptomic approaches were used to compare the lipid accumulation between high and low lipid content cacao accessions. Lipid accumulation rates and lipid content were different between the two accessions. Moreover, differentially expressed genes were detected between high and low lipid content cacao accessions. The data allowed the identification of distinct candidate genes and furthered our understanding of lipid accumulation, potentially explaining the differences in lipid content between various cacao accessions. The results might be used to develop molecular tools and engineer alternative pathways for cacao breeding with improved lipid production potentials.

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Sugarcane Distillery Spent Wash, a New Resource for Third-Generation Biodiesel Production

Water ◽

10.3390/w10111623 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1623 ◽

Cited By ~ 6

Author(s):

Julien Hoarau ◽

Isabelle Grondin ◽

Yanis Caro ◽

Thomas Petit

Keyword(s):

Low Cost ◽

Lipid Production ◽

Liquid Waste ◽

Fungal Growth ◽

Dry Weight ◽

Biodiesel Production ◽

Aspergillus Awamori ◽

Cryptococcus Curvatus ◽

Spent Wash ◽

Distillery Spent Wash

Industrial production of biodiesel from microbial catalysts requires large volume of low-cost feedstock for lipid production. Vinasse, also known as distillery spent wash (DSW), is a liquid waste produced in large amounts by ethanol distilleries. This effluent is particularly rich in organic matter, and may be considered as a potential resource for the production of fungal lipids. The present study aimed at evaluating the potential of vinasse from a distillery located in Reunion Island for yeast and fungal growth, lipid production, and suitability for biodiesel requirements. Among the 28 different strains tested, we found that Aspergillus niger grown on pure vinasse allowed biomass production of up to 24.05 g/L (dry weight), whereas Aspergillus awamori produced the maximum amount of lipid, at 2.27 g/L. Nutrient removal and vinasse remediation were found to be the best for A. niger and Cryptococcus curvatus, reaching a maximum of 50% for nitrogen, and A. awamori showed 50% carbon removal. Lipids produced were principally composed of C16:0, C18:1 (n-9), and C18:2 (n-6), thus resembling the vegetal oil used in the biodiesel production. This work has shown that vinasse can support production of biomass and lipids from fungi and yeast suitable for energetic use and that its polluting charge can be significantly reduced through this process.

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