Green Microalgae Strain Improvement for the Production of Sterols and Squalene
Sterols and squalene are essential biomolecules required for the homeostasis of eukaryotic membrane permeability and fluidity. Both compounds have beneficial effects on human health. As the current sources of sterols and squalene are plant and shark oils, microalgae are suggested as more sustainable...
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| Format: | Article |
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MDPI AG
2021-08-01
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| Series: | Plants |
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| Online Access: | https://www.mdpi.com/2223-7747/10/8/1673 |
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| author | Supakorn Potijun Suparat Jaingam Nuttha Sanevas Srunya Vajrodaya Anchalee Sirikhachornkit |
| author_facet | Supakorn Potijun Suparat Jaingam Nuttha Sanevas Srunya Vajrodaya Anchalee Sirikhachornkit |
| author_sort | Supakorn Potijun |
| collection | DOAJ |
| description | Sterols and squalene are essential biomolecules required for the homeostasis of eukaryotic membrane permeability and fluidity. Both compounds have beneficial effects on human health. As the current sources of sterols and squalene are plant and shark oils, microalgae are suggested as more sustainable sources. Nonetheless, the high costs of production and processing still hinder the commercialization of algal cultivation. Strain improvement for higher product yield and tolerance to harsh environments is an attractive way to reduce costs. Being an intermediate in sterol synthesis, squalene is converted to squalene epoxide by squalene epoxidase. This step is inhibited by terbinafine, a commonly used antifungal drug. In yeasts, some terbinafine-resistant strains overproduced sterols, but similar microalgae strains have not been reported. Mutants that exhibit greater tolerance to terbinafine might accumulate increased sterols and squalene content, along with the ability to tolerate the drug and other stresses, which are beneficial for outdoor cultivation. To explore this possibility, terbinafine-resistant mutants were isolated in the model green microalga <i>Chlamydomonas reinhardtii</i> using UV mutagenesis. Three mutants were identified and all of them exhibited approximately 50 percent overproduction of sterols. Under terbinafine treatment, one of the mutants also accumulated around 50 percent higher levels of squalene. The higher accumulation of pigments and triacylglycerol were also observed. Along with resistance to terbinafine, this mutant also exhibited higher resistance to oxidative stress. Altogether, resistance to terbinafine can be used to screen for strains with increased levels of sterols or squalene in green microalgae without growth compromise. |
| first_indexed | 2024-03-10T08:27:22Z |
| format | Article |
| id | doaj.art-7221d32388e54e8298acca8d122531e7 |
| institution | Directory Open Access Journal |
| issn | 2223-7747 |
| language | English |
| last_indexed | 2024-03-10T08:27:22Z |
| publishDate | 2021-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Plants |
| spelling | doaj.art-7221d32388e54e8298acca8d122531e72023-11-22T09:19:55ZengMDPI AGPlants2223-77472021-08-01108167310.3390/plants10081673Green Microalgae Strain Improvement for the Production of Sterols and SqualeneSupakorn Potijun0Suparat Jaingam1Nuttha Sanevas2Srunya Vajrodaya3Anchalee Sirikhachornkit4Department of Genetics, Faculty of Science, Kasetsart University, Bangkok 10900, ThailandDepartment of Genetics, Faculty of Science, Kasetsart University, Bangkok 10900, ThailandDepartment of Botany, Faculty of Science, Kasetsart University, Bangkok 10900, ThailandDepartment of Botany, Faculty of Science, Kasetsart University, Bangkok 10900, ThailandDepartment of Genetics, Faculty of Science, Kasetsart University, Bangkok 10900, ThailandSterols and squalene are essential biomolecules required for the homeostasis of eukaryotic membrane permeability and fluidity. Both compounds have beneficial effects on human health. As the current sources of sterols and squalene are plant and shark oils, microalgae are suggested as more sustainable sources. Nonetheless, the high costs of production and processing still hinder the commercialization of algal cultivation. Strain improvement for higher product yield and tolerance to harsh environments is an attractive way to reduce costs. Being an intermediate in sterol synthesis, squalene is converted to squalene epoxide by squalene epoxidase. This step is inhibited by terbinafine, a commonly used antifungal drug. In yeasts, some terbinafine-resistant strains overproduced sterols, but similar microalgae strains have not been reported. Mutants that exhibit greater tolerance to terbinafine might accumulate increased sterols and squalene content, along with the ability to tolerate the drug and other stresses, which are beneficial for outdoor cultivation. To explore this possibility, terbinafine-resistant mutants were isolated in the model green microalga <i>Chlamydomonas reinhardtii</i> using UV mutagenesis. Three mutants were identified and all of them exhibited approximately 50 percent overproduction of sterols. Under terbinafine treatment, one of the mutants also accumulated around 50 percent higher levels of squalene. The higher accumulation of pigments and triacylglycerol were also observed. Along with resistance to terbinafine, this mutant also exhibited higher resistance to oxidative stress. Altogether, resistance to terbinafine can be used to screen for strains with increased levels of sterols or squalene in green microalgae without growth compromise.https://www.mdpi.com/2223-7747/10/8/1673biodiesel<i>Chlamydomonas</i>squalenesterolterbinafine |
| spellingShingle | Supakorn Potijun Suparat Jaingam Nuttha Sanevas Srunya Vajrodaya Anchalee Sirikhachornkit Green Microalgae Strain Improvement for the Production of Sterols and Squalene Plants biodiesel <i>Chlamydomonas</i> squalene sterol terbinafine |
| title | Green Microalgae Strain Improvement for the Production of Sterols and Squalene |
| title_full | Green Microalgae Strain Improvement for the Production of Sterols and Squalene |
| title_fullStr | Green Microalgae Strain Improvement for the Production of Sterols and Squalene |
| title_full_unstemmed | Green Microalgae Strain Improvement for the Production of Sterols and Squalene |
| title_short | Green Microalgae Strain Improvement for the Production of Sterols and Squalene |
| title_sort | green microalgae strain improvement for the production of sterols and squalene |
| topic | biodiesel <i>Chlamydomonas</i> squalene sterol terbinafine |
| url | https://www.mdpi.com/2223-7747/10/8/1673 |
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