Phaeodactylum tricornutum microalgae as a rich source of omega-3 oil: Progress in lipid induction techniques towards industry adoption

Abstract Background: Oleaginous microalgae represent a valuable resource for the production of high value molecules. Considering the importance of omega-3 long chain polyunsaturated fatty acids (LC-PUFAs) for human health and nutrition the yields of high value eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) require significant improvement to meet demand, however, the current cost of production remains high. A promising approach is to metabolically engineer strains with enhanced levels of triacylglycerols (TAGs) enriched in EPA and DHA.Results: Recently we have engineered the marine diatom Phaeodactylum tricornutum to accumulate enhanced levels of DHA in TAG. To further improve the incorporation of omega-3 LC-PUFAs in TAG we focused our effort on the identification of a type 2 acyl-CoA:diacylglycerol acyltransferase (DGAT) capable of improving lipid production and the incorporation of DHA in TAG. DGAT is a key enzyme in lipid synthesis. Following a diatom based in vivo screen of candidate DGATs, a native P. tricornutum DGAT2B was taken forward for detailed characterisation. Overexpression of the endogenous P. tricornutum DGAT2B was confirmed by qRT-PCR and the transgenic strain grew successfully in comparison to wildtype. PtDGAT2B has broad substrate specificity with preferences for C16 and LC-PUFAs acyl groups. Moreover, the overexpression of an endogenous DGAT2B resulted in higher lipid yields and enhanced levels of DHA in TAG. Furthermore, a combined overexpression of the endogenous DGAT2B and ectopic expression of a Δ5-elongase showed how iterative metabolic engineering can be used to increase DHA and TAG content, irrespective of nitrogen treatment.Conclusion: This study provides further insight into lipid metabolism in P. tricornutum and suggests a metabolic engineering approach for the efficient production of EPA and DHA in microalgae.

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Shrimp Oil Extracted from Shrimp Processing By-Product Is a Rich Source of Omega-3 Fatty Acids and Astaxanthin-Esters, and Reveals Potential Anti-Adipogenic Effects in 3T3-L1 Adipocytes

Marine Drugs ◽

10.3390/md19050259 ◽

2021 ◽

Vol 19 (5) ◽

pp. 259

Author(s):

Indrayani Phadtare ◽

Hitesh Vaidya ◽

Kelly Hawboldt ◽

Sukhinder Kaur Cheema

Keyword(s):

Fatty Acids ◽

Mrna Expression ◽

Glucose Transporter ◽

Rich Source ◽

Omega 3 ◽

Fat Accumulation ◽

Lipogenic Genes ◽

Expression Of Genes ◽

Soxhlet Method ◽

Shrimp Oil

The province of Newfoundland and Labrador, Canada, generates tons of shrimp processing by-product every year. Shrimp contains omega (n)-3 polyunsaturated fatty acids (PUFA) and astaxanthin (Astx), a potent antioxidant that exists in either free or esterified form (Astx-E). In this study, shrimp oil (SO) was extracted from the shrimp processing by-product using the Soxhlet method (hexane:acetone 2:3). The extracted SO was rich in phospholipids, n-3 PUFA, and Astx-E. The 3T3-L1 preadipocytes were differentiated to mature adipocytes in the presence or absence of various treatments for 8 days. The effects of SO were then investigated on fat accumulation, and the mRNA expression of genes involved in adipogenesis and lipogenesis in 3T3-L1 cells. The effects of fish oil (FO), in combination with Astx-E, on fat accumulation, and the mRNA expression of genes involved in adipogenesis and lipogenesis were also investigated. The SO decreased fat accumulation, compared to untreated cells, which coincided with lower mRNA expression of adipogenic and lipogenic genes. However, FO and FO + Astx-E increased fat accumulation, along with increased mRNA expression of adipogenic and lipogenic genes, and glucose transporter type 4 (Glut-4), compared to untreated cells. These findings have demonstrated that the SO is a rich source of n-3 PUFA and Astx-E, and has the potential to elicit anti-adipogenic effects. Moreover, the SO and FO appear to regulate adipogenesis and lipogenesis via independent pathways in 3T3-L1 cells.

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Co-cultivation of Phaeodactylum tricornutum and Aurantiochytrium limacinum for polyunsaturated omega-3 fatty acids production

Bioresource Technology ◽

10.1016/j.biortech.2021.126544 ◽

2021 ◽

pp. 126544

Author(s):

Nikhil L. Kadalag ◽

Pratik R. Pawar ◽

Gunjan Prakash

Keyword(s):

Fatty Acids ◽

Phaeodactylum Tricornutum ◽

Omega 3 Fatty Acids ◽

Omega 3

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Towards the Industrial Production of Omega-3 Long Chain Polyunsaturated Fatty Acids from a Genetically Modified Diatom Phaeodactylum tricornutum

PLoS ONE ◽

10.1371/journal.pone.0144054 ◽

2015 ◽

Vol 10 (12) ◽

pp. e0144054 ◽

Cited By ~ 48

Author(s):

Mary L. Hamilton ◽

Joanna Warwick ◽

Anya Terry ◽

Michael J. Allen ◽

Johnathan A. Napier ◽

...

Keyword(s):

Fatty Acids ◽

Polyunsaturated Fatty Acids ◽

Industrial Production ◽

Phaeodactylum Tricornutum ◽

Genetically Modified ◽

Omega 3 ◽

Long Chain

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Oral Bioavailability of Omega-3 Fatty Acids and Carotenoids from the Microalgae Phaeodactylum tricornutum in Healthy Young Adults

Marine Drugs ◽

10.3390/md19120700 ◽

2021 ◽

Vol 19 (12) ◽

pp. 700

Author(s):

Lena Stiefvatter ◽

Katja Lehnert ◽

Konstantin Frick ◽

Alexander Montoya-Arroyo ◽

Jan Frank ◽

...

Keyword(s):

Fatty Acids ◽

Phaeodactylum Tricornutum ◽

Omega 3 Fatty Acids ◽

Omega 3 ◽

Sustainable Food ◽

Epa And Dha ◽

Beta Glucans ◽

Randomized Intervention ◽

Safety Parameters ◽

Sea Fish

The microalgae Phaeodactylum tricornutum (PT) contains valuable nutrients such as proteins, polyunsaturated omega-3 fatty acids (n-3 PUFA), particularly eicosapentaenoic acid (EPA) and some docosahexaenoic acid (DHA), carotenoids such as fucoxanthin (FX), and beta-glucans, which may confer health benefits. In a randomized intervention trial involving 22 healthy individuals, we administered for two weeks in a crossover manner the whole biomass of PT (5.3 g/day), or fish oil (FO) containing equal amounts of EPA and DHA (together 300 mg/day). In an additional experiment, sea fish at 185 g/week resulting in a similar EPA and DHA intake was administered in nine individuals. We determined the bioavailability of fatty acids and carotenoids and assessed safety parameters. The intake of PT resulted in a similar increase in the n-3 PUFA and EPA content and a decrease in the PUFA n-6:n-3 ratio in plasma. PT intake caused an uptake of FX that is metabolized to fucoxanthinol (FXOH) and amarouciaxanthin A (AxA). No relevant adverse effects occurred following PT consumption. The study shows that PT is a safe and effective source of EPA and FX—and likely other nutrients—and therefore should be considered as a future sustainable food item.

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Overexpression of a type 2 diacylglycerol acyltransferase in the marine diatom Phaeodactylum tricornutum enhances lipid production and omega-3 Long Chain Polyunsaturated Fatty Acid content

10.21203/rs.2.21513/v1 ◽

2020 ◽

Author(s):

Richard P. Haslam ◽

Mary L. Hamilton ◽

Chloe K. Economou ◽

Richard Smith ◽

Kirsty L. Hassall ◽

...

Keyword(s):

Metabolic Engineering ◽

Phaeodactylum Tricornutum ◽

Lipid Production ◽

Marine Diatom ◽

Efficient Production ◽

Omega 3 ◽

Oleaginous Microalgae ◽

Epa And Dha ◽

Long Chain

Abstract Background: Oleaginous microalgae represent a valuable resource for the production of high value molecules. Considering the importance of omega-3 long chain polyunsaturated fatty acids (LC-PUFAs) for human health and nutrition the yields of high value eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) require significant improvement to meet demand, however, the current cost of production remains high. A promising approach is to metabolically engineer strains with enhanced levels of triacylglycerols (TAGs) enriched in EPA and DHA. Results: Recently we have engineered the marine diatom Phaeodactylum tricornutum to accumulate enhanced levels of DHA in TAG. To further improve the incorporation of omega-3 LC-PUFAs in TAG we focused our effort on the identification of a type 2 acyl-CoA:diacylglycerol acyltransferase (DGAT) capable of improving lipid production and the incorporation of DHA in TAG. DGAT is a key enzyme in lipid synthesis. Following a diatom based in vivo screen of candidate DGATs, a native P. tricornutum DGAT2B was taken forward for detailed characterisation. Expression of DGAT2B in P. tricornutum was confirmed by qRT-PCR and the transgenic strain grew successfully in comparison to wildtype. PtDGAT2B has broad substrate specificity with preferences for C16 and LC-PUFAs acyl groups. Moreover, the expression of DGAT2B resulted in higher lipid yields and enhanced levels of DHA in TAG. Furthermore, co-expression with a Δ5-elongase showed how iterative metabolic engineering can be used to increase DHA and TAG content, irrespective of nitrogen treatment.Conclusion: This study provides further insight into lipid metabolism in P. tricornutum and suggests a metabolic engineering approach for the efficient production of EPA and DHA in microalgae.

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