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Jo Shu Chang - One of the best experts on this subject based on the ideXlab platform.
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feasibility of co2 mitigation and carbohydrate production by Microalga scenedesmus obliquus cnw n used for bioethanol fermentation under outdoor conditions effects of seasonal changes
Biotechnology for Biofuels, 2017Co-Authors: Yi Di Chen, Chun Yen Chen, Nanqi Ren, Ching Yu Chang, Yen Ying Lai, Akihiko Kondo, Jo Shu ChangAbstract:Although outdoor cultivation systems have been widely used for mass production of Microalgae at a relatively low cost, there are still limited efforts on outdoor cultivation of carbohydrate-rich Microalgae that were further used as feedstock for fermentative bioethanol production. In particular, the effects of seasonal changes on cell growth, CO2 fixation, and carbohydrate production of the Microalgae have not been well investigated. This work demonstrates the feasibility of using outdoor tubular photobioreactors (PBR) for whole-year-round cultivation of a carbohydrate-rich Microalga Scenedesmus obliquus CNW-N in southern Taiwan. Time-course profile of the carbohydrate content under nitrogen-deficient conditions was monitored to assess the seasonal changes. The optimal CO2 fixation rate and carbohydrate productivity were 430.2 mg L−1 d−1and 111.8 mg L−1d−1, respectively, which were obtained during the summer time. Under nitrogen starvation, the Microalgal biomass can accumulate nearly 45–50% of carbohydrates, mainly composed of glucose that accounted for 70–80% of the total carbohydrates in the Microalgal cells. This glucose-rich Microalgal biomass is apparently a very suitable carbon source for bioethanol fermentation. This work shows the feasibility of combining CO2 fixation and bioethanol production using Microalgae grown in outdoor photobioreactors as feedstock. The understanding of the seasonal changes in the carbohydrate productivity makes this approach more practically viable. The novel strategy proposed in this study could be a promising alternative to the existing technology dealing with CO2 mitigation and biofuels production.
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Wet torrefaction of Microalga Chlorella vulgaris ESP-31 with microwave-assisted heating
Energy Conversion and Management, 2017Co-Authors: Quang-vu Bach, Wei Hsin Chen, Shih Cheng Lin, Herng Kuang Sheen, Jo Shu ChangAbstract:Abstract Microalgae are a prime source of third generation biofuels. Many thermochemical processes can be applied to convert them into fuels and other valuable products. However, some types of Microalgae are characterized by very high moisture and ash contents, thereby causing several problems in further conversion processes. This study presents wet torrefaction (WT) as a promising pretreatment method to overcome the aforementioned drawbacks coupled with Microalgal biomass. For this purpose, a microwave-assisted heating system was used for WT of Microalga Chlorella vulgaris ESP-31 at different reaction temperatures (160, 170, and 180 °C) and durations (5, 10, and 30 min). The results show several improvements in the fuel properties of the Microalga after WT such as increased calorific value and hydrophobicity as well as reduced ash content. A correlation in terms of elemental analysis can be adopted to predict the higher heating value of the torrefied Microalga. The structure analysis by Fourier transform infrared (FT-IR) spectroscopy reveals that the carbohydrate content in the torrefied Microalgae is lowered, whereas their protein and lipid contents are increased if the WT extent is not severe. However, the protein and lipid contents are reduced significantly at more severe WT conditions. The thermogravimetric analysis shows that the torrefied Microalgae have lower ignition temperatures but higher burnout temperatures than the raw Microalga, revealing significant impact of WT on the combustion reactivity of the Microalga. Overall, the calorific value of the Microalga can be intensified up to 21%, and at least 61.5% of energy in the biomass is retained after WT.
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Effect of Wet Torrefaction on Thermal Decomposition Behavior of Microalga Chlorella vulgaris ESP-31
Energy Procedia, 2017Co-Authors: Quang-vu Bach, Wei Hsin Chen, Shih Cheng Lin, Herng Kuang Sheen, Jo Shu ChangAbstract:Abstract In this work, thermal decompositions of wet torrefied Microalga during pyrolysis and combustion are investigated. Microalga Chlorella vulgaris ESP-31 was first subjected to wet torrefaction with microwave-assisted heating. Then, the thermal decompositions of the raw and torrefied Microalgae are studied by means of a thermogravimetric analyzer in nitrogen and synthetic air to simulate pyrolysis and combustion process, respectively. The results show that carbohydrate and protein are degraded to some extent during WT. In addition, thermal reactivity of lipid is also changed after WT. The changes in the Microalgal composition affect the intensity and location of the corresponding peaks during pyrolysis and combustion. Moreover, the char produced from the raw Microalga is more reactive and less stable than those from the torrefied microlagae.
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cultivation of chlorella vulgaris jsc 6 with swine wastewater for simultaneous nutrient cod removal and carbohydrate production
Bioresource Technology, 2015Co-Authors: Yue Wang, Jo Shu Chang, Wanqian Guo, Hongwei Yen, Chieh Lun Cheng, Nanqi RenAbstract:Swine wastewater, containing a high concentration of COD and ammonia nitrogen, is suitable for the growth of Microalgae, leading to simultaneous COD/nutrients removal from the wastewater. In this study, an isolated carbohydrate-rich Microalga Chlorella vulgaris JSC-6 was adopted to perform swine wastewater treatment. Nearly 60-70% COD removal and 40-90% NH3-N removal was achieved in the mixotrophic and heterotrophic culture, depending on the dilution ratio of the wastewater, while the highest removal percentage was obtained with 20-fold diluted wastewater. Mixotrophic cultivation by using fivefold diluted wastewater resulted in the highest biomass concentration of 3.96 g/L. The carbohydrate content of the Microalga grown on the wastewater can reach up to 58% (per dry weight). The results indicated that the Microalgae-based wastewater treatment can efficiently reduce the nutrients and COD level, and the resulting Microalgal biomass had high carbohydrate content, thereby having potential applications for the fermentative production of biofuels or chemicals.
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characterization of the flocculating agent from the spontaneously flocculating Microalga chlorella vulgaris jsc 7
Journal of Bioscience and Bioengineering, 2014Co-Authors: Md. Asraful Alam, Zihyou Huang, Yuliang Yang, Xinqing Zhao, Jo Shu ChangAbstract:High cost of biomass recovery is one of the bottlenecks for developing cost-effective processes with Microalgae, particularly for the production of biofuels and bio-based chemicals through biorefinery, and Microalgal biomass recovery through cell flocculation is a promising strategy. Some Microalgae are naturally flocculated whose cells can be harvested by simple sedimentation. However, studies on the flocculating agents synthesized by Microalgae cells are still very limited. In this work, the cell flocculation of a spontaneously flocculating Microalga Chlorella vulgaris JSC-7 was studied, and the flocculating agent was identified to be cell wall polysaccharides whose crude extract supplemented at low dosage of 0.5 mg/L initiated the more than 80% flocculating rate of freely suspended Microalgae C. vulgaris CNW11 and Scenedesmus obliquus FSP. Fourier transform infrared (FTIR) analysis revealed a characteristic absorption band at 1238 cm−1, which might arise from P O asymmetric stretching vibration of PO 2 − phosphodiester. The unique cell wall-associated polysaccharide with molecular weight of 9.86×103 g/mol, and the monomers consist of glucose, mannose and galactose with a molecular ratio of 5:5:2. This is the first time to our knowledge that the flocculating agent from C. vulgaris has been characterized, which could provide basis for understanding the cell flocculation of Microalgae and breeding of novel flocculating Microalgae for cost-effective biomass harvest.
Yoav Bashan - One of the best experts on this subject based on the ideXlab platform.
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role of glutamate dehydrogenase and glutamine synthetase in chlorella vulgaris during assimilation of ammonium when jointly immobilized with the Microalgae growth promoting bacterium azospirillum brasilense 1
Journal of Phycology, 2008Co-Authors: Luz E Debashan, Paola Magallon, Hani Antoun, Yoav BashanAbstract:Enzymatic activities of glutamate dehydrogenase (GDH) and glutamine synthetase (GS) participating in the nitrogen metabolism and related ammonium absorption were assayed after the Microalga Chlorella vulgaris Beij. was jointly immobilized with the Microalgae-growth-promoting bacterium Azospirillum brasilense. At initial concentrations of 3, 6, and 10 mg · L−1 NH4+, joint immobilization enhances growth of C. vulgaris but does not affect ammonium absorption capacity of the Microalga. However, at 8 mg · L−1 NH4+, joint immobilization enhanced ammonium absorption by the Microalga without affecting the growth of the Microalgal population. Correlations between absorption of ammonium per cell and per culture showed direct (negative and positive) linear correlations between these parameters and Microalga populations at 3, 6, and 10 mg · L−1 NH4+, but not at 8 mg · L−1 NH4+, where the highest absorption of ammonium occurred. In all cultures, immobilized and jointly immobilized, having the four initial ammonium concentrations, enzymatic activities of Chlorella are affected by A. brasilense. Regardless of the initial concentration of ammonium, GS activity in C. vulgaris was always higher when jointly immobilized and determined on a per-cell basis. When jointly immobilized, only at an initial concentration of 8 mg · L−1 NH4+ was GDH activity per cell higher.
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Changes in the metabolism of the Microalga Chlorella vulgaris when coimmobilized in alginate with the nitrogen-fixing Phyllobacterium myrsinacearum.
Canadian journal of microbiology, 2000Co-Authors: Luz E. Gonzalez-bashan, Vladimir Lebsky, Juan Pablo Hernández, Jose J. Bustillos, Yoav BashanAbstract:In an agroindustrial wastewater pond, a naturally occurring unicellular Microalga, Chlorella vulgaris, was closely associated with the terrestrial plant-associative N2-fixing bacterium Phyllobacterium myrsinacearum. When the two microorganisms were artificially coimmobilized in alginate beads, they shared the same internal bead cavities, and the production of five Microalgal pigments increased, but there were no effects on the number of the cells or the biomass of the Microalga. The association, however, reduces the ability of C. vulgaris to remove ammonium ions and phosphorus from water. The bacterium produced nitrate from ammonium in synthetic wastewater with or without the presence of the Microalga, and fixed nitrogen in two culture media. Our results suggest that interactions between Microalgae and associative bacteria should be considered when cultivating Microalgae for wastewater treatment.
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increased growth of the Microalga chlorella vulgaris when coimmobilized and cocultured in alginate beads with the plant growth promoting bacterium azospirillum brasilense
Applied and Environmental Microbiology, 2000Co-Authors: Luz E Gonzalez, Yoav BashanAbstract:Coimmobilization of the freshwater Microalga Chlorella vulgaris and the plant-growth-promoting bacterium Azospirillum brasilense in small alginate beads resulted in a significantly increased growth of the Microalga. Dry and fresh weight, total number of cells, size of the Microalgal clusters (colonies) within the bead, number of Microalgal cells per cluster, and the levels of Microalgal pigments significantly increased. Light microscopy revealed that both microorganisms colonized the same cavities inside the beads, though the Microalgae tended to concentrate in the more aerated periphery while the bacteria colonized the entire bead. The effect of indole-3-acetic acid addition to Microalgal culture prior to immobilization of microorganisms in alginate beads partially imitated the effect of A. brasilense. We propose that coimmobilization of Microalgae and plant-growth-promoting bacteria is an effective means of increasing Microalgal populations within confined environments.
Wipa Chungjatupornchai - One of the best experts on this subject based on the ideXlab platform.
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Accelerated triacylglycerol production and altered fatty acid composition in oleaginous Microalga Neochloris oleoabundans by overexpression of diacylglycerol acyltransferase 2
Microbial Cell Factories, 2017Co-Authors: Paeka Klaitong, Sirirat Fa-aroonsawat, Wipa ChungjatupornchaiAbstract:Background Microalgae are promising sources of lipid triacylglycerol (TAG) for biodiesel production. However, to date, Microalgal biodiesel is technically feasible, but not yet economically viable. Increasing TAG content and productivity are important to achieve economic viability of Microalgal biodiesel. To increase TAG content, oleaginous Microalga Neochloris oleoabundans was genetically engineered with an endogenous key enzyme diacylglycerol acyltransferase 2 (NeoDGAT2) responsible for TAG biosynthesis.
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Accelerated triacylglycerol production and altered fatty acid composition in oleaginous Microalga Neochloris oleoabundans by overexpression of diacylglycerol acyltransferase 2
Microbial Cell Factories, 2017Co-Authors: Paeka Klaitong, Sirirat Fa-aroonsawat, Wipa ChungjatupornchaiAbstract:Background Microalgae are promising sources of lipid triacylglycerol (TAG) for biodiesel production. However, to date, Microalgal biodiesel is technically feasible, but not yet economically viable. Increasing TAG content and productivity are important to achieve economic viability of Microalgal biodiesel. To increase TAG content, oleaginous Microalga Neochloris oleoabundans was genetically engineered with an endogenous key enzyme diacylglycerol acyltransferase 2 (NeoDGAT2) responsible for TAG biosynthesis. Results The integration of NeoDGAT2 expression cassettes in N. oleoabundans transformant was confirmed by PCR. The neutral lipid accumulation in the transformant detected by Nile red staining was accelerated and 1.9-fold higher than in wild type; the lipid bodies in the transformant visualized under fluorescence microscope were also larger. The NeoDGAT2 transcript was two-fold higher in the transformant than wild type. Remarkably higher lipid accumulation was found in the transformant than wild type: total lipid content increased 1.6-to 2.3-fold up to 74.5 ± 4.0% dry cell weight (DCW) and total lipid productivity increased 1.6- to 3.2-fold up to 14.6 ± 2.0 mg/L/day; while TAG content increased 1.8- to 3.2-fold up to 46.1 ± 1.6% DCW and TAG productivity increased 1.6- to 4.3-fold up to 8.9 ± 1.3 mg/L/day. A significantly altered fatty acid composition was detected in the transformant compared to wild type; the levels of saturated fatty acid C16:0 increased double to 49%, whereas C18:0 was reduced triple to 6%. Long-term stability was observed in the transformant continuously maintained in solid medium over 100 generations in a period of about 4 years. Conclusions Our results demonstrate the increased TAG content and productivity in N. oleoabundans by NeoDGAT2 overexpression that may offer the first step towards making Microalgae an economically feasible source for biodiesel production. The strategy for genetically improved Microalga presented in this study can be applied to other Microalgal species possessing desired characteristics for industrial biofuel production.
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Stable nuclear transformation of the oleaginous Microalga Neochloris oleoabundans by electroporation
Journal of Applied Phycology, 2015Co-Authors: Wipa Chungjatupornchai, Paweena Kitraksa, Sirirat Fa-aroonsawatAbstract:Biodiesel from Microalgae is technically feasible, but not yet economically viable. A potential approach to improve Microalgae as an economically viable biodiesel feedstock is to increase Microalgal lipid content via genetic engineering. Genetic manipulation of Microalgae requires the accessibility to stable nuclear transformation. In this study, we describe a strategy for developing a stable nuclear transformation system of the oleaginous Microalga Neochloris oleoabundans using electroporation. The hygromycin B-resistant gene Hyg3, which was used as a positively selectable marker, consisted of aph7” gene encoding aminoglycoside phosphotransferase of Streptomyces hygroscopicus and intron1 of Chlamydomonas reinhardtii rbcS2 gene, under the control of C. reinhardtii HSP70A-RBCS2 hybrid promoter. The transformation frequency was 5.2 × 10−4 transformants mg−1 DNA. The transformants showed stable hygromycin B-resistant phenotype for at least 6 months in the absence of the antibiotic selection. Co-transformation frequency of unselectable green fluorescent protein gene (Gfp) adapted to C. reinhardtii codon usage (ChGfp) and selectable Hyg3 gene was 2.6 × 10−4 transformants mg−1 DNA; up to 90 % of the transformants exhibited green fluorescent protein (GFP) activity. The ChGfp and Hyg3 gene were integrated into the nuclear genome of N. oleoabundans. The GFP fluorescence signal of the transformants under confocal laser scanning microscope was visible. The successful stable nuclear transformation system not only provides a basis for molecular genetics study, but also enables subsequent genetic engineering in the Microalga to increase lipid content for biodiesel production. The strategy for developing the stable nuclear transformation system presented in this study may be applicable to other Microalgal species without sequenced genome.
Koenraad Muylaert - One of the best experts on this subject based on the ideXlab platform.
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Potential of garlic oil to control biological contamination of Chlamydomonas cultures by the ciliate Oxytricha
Journal of Applied Phycology, 2019Co-Authors: Dries Vandamme, Koenraad MuylaertAbstract:Facilities for the production of Microalgal biomass often suffer large losses in productivity as a result of biological contamination of cultures by ciliates, unicellular protozoans that feed on Microalgae. Garlic oil is a low-cost natural product that is known to be active against several protozoans. In this study, we investigated whether garlic oil can be used to control ciliate contamination in Microalgal cultures, using the ciliate Oxytricha and the Microalga Chlamydomonas as a model system. Low doses of garlic oil (5–10 mg L^−1) were capable of eradicating the ciliate Oxytricha from a contaminated Chlamydomonas culture within 1 day without influencing the productivity of the Chlamydomonas culture. The LD_50 of garlic oil to the ciliate (3 mg L^−1) was 19 times lower than the LD_50 to the Microalgae, which implies a low risk to the Microalgal culture in case of overdosing. Analysis of the garlic oil indicated that it was composed mainly of polysulfides, with the main compound being diallyl disulfide. Diallyl disulfide had a lower toxicity to the ciliate (LD_50 14 mg L^−1) than garlic oil, indicating that diallyl disulfide is not the main active compound in garlic oil against the ciliate. Because garlic oil has a low cost, is already approved for use in agri- and aquacultures, has a low toxicity to humans, and is biodegradable, it may offer a sustainable solution to control biological contamination by ciliates in Microalgal cultures.
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Biological control of ciliate contamination in Chlamydomonas culture using the predatory copepod Acanthocyclops robustus
Algal Research, 2019Co-Authors: Thi Kim Hue Nguyen, Bert Deruyck, Ellen Decaestecker, Dries Vandamme, Koenraad MuylaertAbstract:Abstract Ciliates are a common but less-explored group of contaminants in Microalgal cultures that feed on Microalgae and can cause severe losses in productivity of cultures. The aim of this study was to evaluate the potential of biological control to eradicate ciliates from Microalgal cultures. In lab-scale experiments, we used the carnivorous cyclopoid copepod Acanthocyclops robustus as a biological control agent to eliminate the ciliate Sterkiella from cultures of the Microalga Chlamydomonas. Our experiments showed that the copepod Acanthocyclops robustus can consume up to 400 ciliates individual−1 day−1. Addition of 0.07 copepods mL−1 to a culture that was contaminated with 10 ciliates mL−1 resulted in a complete elimination of ciliates from the culture within 1 day and restored the algal biomass production at the level of a non-contaminated culture. Addition of copepods to a fresh Chlamydomonas culture did not cause a reduction in the Microalgal biomass concentration, indicating that this copepod does not feed on Chlamydomonas. These laboratory-scale experiments indicate that copepods have potential to be used as a biological control agent to address the problem of contamination of large-scale Microalgal cultures by ciliates.
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evaluation of the volatile composition and sensory properties of five species of Microalgae
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Jim Van Durme, Koen Goiris, Ann De Winne, Luc De Cooman, Koenraad MuylaertAbstract:Due to their high content of polyunsaturated fatty acids, antioxidants, and proteins, Microalgae hold a lot of potential for nutritional applications. When Microalgae are integrated into foodstuffs, the aroma is an important aspect to consider. In this study the aroma properties of Microalgae were studied by correlating data on the volatile composition with sensory evaluations. Four species of marine Microalgae (Botryococcus braunii,, Rhodomonas, Tetraselmis species, and Nannochloropsis oculata) and one fresh water Microalga (Chlorella vulgaris) were investigated. Multivariate data processing revealed that Microalgal samples having a seafood-like odor character contain high levels of sulfuric compounds (dimethyl disulfide, dimethyl trisulfide, and methional), diketones, α-ionone, and β-ionone. Fresh green, fruity flavors were linked with typical aldehydes such as 2,4-alkadienals and 2,4,6-alkatrienals. The presence of these compounds in fresh Microalga pastes is explained by aroma formation mechanisms suc...
Sirirat Fa-aroonsawat - One of the best experts on this subject based on the ideXlab platform.
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Accelerated triacylglycerol production and altered fatty acid composition in oleaginous Microalga Neochloris oleoabundans by overexpression of diacylglycerol acyltransferase 2
Microbial Cell Factories, 2017Co-Authors: Paeka Klaitong, Sirirat Fa-aroonsawat, Wipa ChungjatupornchaiAbstract:Background Microalgae are promising sources of lipid triacylglycerol (TAG) for biodiesel production. However, to date, Microalgal biodiesel is technically feasible, but not yet economically viable. Increasing TAG content and productivity are important to achieve economic viability of Microalgal biodiesel. To increase TAG content, oleaginous Microalga Neochloris oleoabundans was genetically engineered with an endogenous key enzyme diacylglycerol acyltransferase 2 (NeoDGAT2) responsible for TAG biosynthesis.
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Accelerated triacylglycerol production and altered fatty acid composition in oleaginous Microalga Neochloris oleoabundans by overexpression of diacylglycerol acyltransferase 2
Microbial Cell Factories, 2017Co-Authors: Paeka Klaitong, Sirirat Fa-aroonsawat, Wipa ChungjatupornchaiAbstract:Background Microalgae are promising sources of lipid triacylglycerol (TAG) for biodiesel production. However, to date, Microalgal biodiesel is technically feasible, but not yet economically viable. Increasing TAG content and productivity are important to achieve economic viability of Microalgal biodiesel. To increase TAG content, oleaginous Microalga Neochloris oleoabundans was genetically engineered with an endogenous key enzyme diacylglycerol acyltransferase 2 (NeoDGAT2) responsible for TAG biosynthesis. Results The integration of NeoDGAT2 expression cassettes in N. oleoabundans transformant was confirmed by PCR. The neutral lipid accumulation in the transformant detected by Nile red staining was accelerated and 1.9-fold higher than in wild type; the lipid bodies in the transformant visualized under fluorescence microscope were also larger. The NeoDGAT2 transcript was two-fold higher in the transformant than wild type. Remarkably higher lipid accumulation was found in the transformant than wild type: total lipid content increased 1.6-to 2.3-fold up to 74.5 ± 4.0% dry cell weight (DCW) and total lipid productivity increased 1.6- to 3.2-fold up to 14.6 ± 2.0 mg/L/day; while TAG content increased 1.8- to 3.2-fold up to 46.1 ± 1.6% DCW and TAG productivity increased 1.6- to 4.3-fold up to 8.9 ± 1.3 mg/L/day. A significantly altered fatty acid composition was detected in the transformant compared to wild type; the levels of saturated fatty acid C16:0 increased double to 49%, whereas C18:0 was reduced triple to 6%. Long-term stability was observed in the transformant continuously maintained in solid medium over 100 generations in a period of about 4 years. Conclusions Our results demonstrate the increased TAG content and productivity in N. oleoabundans by NeoDGAT2 overexpression that may offer the first step towards making Microalgae an economically feasible source for biodiesel production. The strategy for genetically improved Microalga presented in this study can be applied to other Microalgal species possessing desired characteristics for industrial biofuel production.
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Stable nuclear transformation of the oleaginous Microalga Neochloris oleoabundans by electroporation
Journal of Applied Phycology, 2015Co-Authors: Wipa Chungjatupornchai, Paweena Kitraksa, Sirirat Fa-aroonsawatAbstract:Biodiesel from Microalgae is technically feasible, but not yet economically viable. A potential approach to improve Microalgae as an economically viable biodiesel feedstock is to increase Microalgal lipid content via genetic engineering. Genetic manipulation of Microalgae requires the accessibility to stable nuclear transformation. In this study, we describe a strategy for developing a stable nuclear transformation system of the oleaginous Microalga Neochloris oleoabundans using electroporation. The hygromycin B-resistant gene Hyg3, which was used as a positively selectable marker, consisted of aph7” gene encoding aminoglycoside phosphotransferase of Streptomyces hygroscopicus and intron1 of Chlamydomonas reinhardtii rbcS2 gene, under the control of C. reinhardtii HSP70A-RBCS2 hybrid promoter. The transformation frequency was 5.2 × 10−4 transformants mg−1 DNA. The transformants showed stable hygromycin B-resistant phenotype for at least 6 months in the absence of the antibiotic selection. Co-transformation frequency of unselectable green fluorescent protein gene (Gfp) adapted to C. reinhardtii codon usage (ChGfp) and selectable Hyg3 gene was 2.6 × 10−4 transformants mg−1 DNA; up to 90 % of the transformants exhibited green fluorescent protein (GFP) activity. The ChGfp and Hyg3 gene were integrated into the nuclear genome of N. oleoabundans. The GFP fluorescence signal of the transformants under confocal laser scanning microscope was visible. The successful stable nuclear transformation system not only provides a basis for molecular genetics study, but also enables subsequent genetic engineering in the Microalga to increase lipid content for biodiesel production. The strategy for developing the stable nuclear transformation system presented in this study may be applicable to other Microalgal species without sequenced genome.
