Optimization of Phototrophic Growth and Lipid Production of a Newly Isolated Microalga, Desmodesmus sp. KAERI-NJ5
2
조회
0
다운로드
5
인용
0
참고문헌
키워드
초록
In this study, a novel microalgal strain, Desmodesmus sp. KAERI-NJ5, was isolated, identified, and evaluated as a candidate for biodiesel feedstock. In a preliminary study, the effects of four general microalgal growth factors, including temperature, pH, light intensity, and concentration of nitrogen source (KNO3), on the microalgal photoautotrophic growth were evaluated. With the exception of light intensity, the growth factors needed to be optimized for the microalgal biomass production. Optimization was done using response surface methodology. The optimal conditions for biomass production were pH 6.54, 27.66℃, and 0.52 g/l KNO3. The biomass production at the optimal conditions was 1.55 g/l, which correlated well with the predicted value of 1.5 g/l. The total lipid and fatty acid methyl ester contents of the cells grown at the optimal conditions were 49% and 21.2% of cell dry weight, respectively. To increase the lipid content of the biomass, microalgae were challenged by nitrogen starvation. Enhancement of total lipid and fatty acid content up to 52.02% and 49%, respectively, were observed. Lipid analysis of the nitrogen-starved cells revealed that C16 and C18 species accounted for 95.9% of the total fatty acids. Among them, palmitic acid (46.17%) and oleic acid (39.43%) dominantly constituted the algal fatty acids. These results suggest Desmodesmus sp. KAERI-NJ5 as a promising feedstock for biodiesel production.
Abstract
In this study, a novel microalgal strain, Desmodesmus sp. KAERI-NJ5, was isolated, identified, and evaluated as a candidate for biodiesel feedstock. In a preliminary study, the effects of four general microalgal growth factors, including temperature, pH, light intensity, and concentration of nitrogen source (KNO3), on the microalgal photoautotrophic growth were evaluated. With the exception of light intensity, the growth factors needed to be optimized for the microalgal biomass production. Optimization was done using response surface methodology. The optimal conditions for biomass production were pH 6.54, 27.66℃, and 0.52 g/l KNO3. The biomass production at the optimal conditions was 1.55 g/l, which correlated well with the predicted value of 1.5 g/l. The total lipid and fatty acid methyl ester contents of the cells grown at the optimal conditions were 49% and 21.2% of cell dry weight, respectively. To increase the lipid content of the biomass, microalgae were challenged by nitrogen starvation. Enhancement of total lipid and fatty acid content up to 52.02% and 49%, respectively, were observed. Lipid analysis of the nitrogen-starved cells revealed that C16 and C18 species accounted for 95.9% of the total fatty acids. Among them, palmitic acid (46.17%) and oleic acid (39.43%) dominantly constituted the algal fatty acids. These results suggest Desmodesmus sp. KAERI-NJ5 as a promising feedstock for biodiesel production.
참고문헌 (32)
- Lang X, "Preparation and characterization of bio-diesels from various bio-oils", Bioresour. Technol, 80, pp.53~62 (2001)
- Greenwell HC, "Placing microalgae on the biofuels priority list: a review of the technological challenges", J. R. Soc. Interface, 7, pp.703~726 (2010)
- Scott SA, "Biodiesel from algae: challenges and prospects", Curr. Opin. Biotechnol, 21, pp.277~286 (2010)
- Chisti Y., "Biodiesel from microalgae beats bioethanol", Trends Biotechnol, 26, pp.126~131 (2008)
- Li YG, "Microalgal biodiesel in China: Opportunities and challenges", Appl. Energy, 88, pp.3432~3437 (2011)
- Chaichalerm S, "Culture of microalgal strains isolated from natural habitats in Thailand in various enriched media", Appl. Energy, 89, pp.296~302 (2012)
- Sharma YC, "Microalgal biodiesel: A possible solution for India’s energy security", Renew. Sustain. Energy Rev, 67, pp.72~78 (2017)
- Sharma YC, "Advancements in development and characterization of biodiesel: A review", Fuel, 12, pp.2355~2373 (2008)
- Chung WS, "A conceptual framework for energy security evaluation of power sources in South Korea", Energy, 137, pp.1066~1074 (2017)
- Hong JW, "Research and development for algae-based technologies in Korea: a review of algae biofuel production", Photosynth. Res, 123, pp.297~303 (2015)
- Nichols HW, "Trichosarcina polymorpha Gen. et Sp. Nov", J. Phycol, 1, pp.34~38 (2007)
- Ren HY, "A new lipid-rich microalga Scenedesmus sp. strain R-16 isolated using Nile red staining: effects of carbon and nitrogen sources and initial pH on the biomass and lipid production", Biotechnol. Biofuels, 6, pp.143~ (2013)
- Hall TA., "BioEdit: a user-friendly biological sequence alignment editor and analysis program for Windows 95", 98, Nucleic Acids Symp. Ser, pp.1999, 41[DOI]
- Saitou N, "The neighbor-joining method: a new method for reconstructing phylogenetic trees", Mol. Biol. Evol, 4, pp.406~425 (1987)
- Tamura K, "MEGA6: Molecular Evolutionary Genetics Analysis Version 6.0", Mol. Biol. Evol, 30, pp.2725~2729 (2013)
- Kimura M., "A simple method for estimating evolutionary rates of base substitutions through comparative studies of nucleotide sequences", J. Mol. Evol, 16, pp.111~120 (1980)
- Felsenstein J., "Confidence limits on phylogenies: An approach using the bootstrap", Evolution, 39, pp.783~791 (1985)
- Prescott DM., "Handling and culturing of Chlorella", pp.159~187 (1964), Academic Press
- Rippka R, "Catalogue & Taxonomic Handbook", pp.103~ (1992), Institut Pasteur
- Vonshak A, "Handbook of microalgal mass culture", pp.117~145 (1986), CRC Press
- Zhu J, "Factors in mass cultivation of microalgae for biodiesel", Chinese J. Catal, 34, pp.80~100 (2013)
- Khozin-Goldberg I, "The effect of phosphate starvation on the lipid and fatty acid composition of the fresh water eustigmatophyte Monodus subterraneus", Phytochemistry, 67, pp.696~701 (2006)
- Butterwick C, "Diversity in the influence of temperature on the growth rates of freshwater algae, and its ecological relevance", Freshw. Biol, 50, pp.291~300 (2005)
- Pan YY, "Isolation of thermo-tolerant and high lipid content green microalgae:Oil accumulation is predominantly controlled by photosystem efficiency during stress treatments in Desmodesmus", Bioresour. Technol, 102, pp.10510~10517 (2011)
- Chiu PH, "Cultivation of two thermotolerant microalgae under tropical conditions: Influences of carbon sources and light duration on biomass and lutein productivity in four seasons", Bioresour. Technol, 212, pp.190~198 (2016)
- Rios LF, "Comparison of growth and lipid accumulation at three different growth regimes with Desmodesmus sp", Waste and Biomass Valorization, 9, pp.421~427 (2018)
- Ji F, "Isolation of a novel microalgae strain Desmodesmus sp. and optimization of environmental factors for its biomass production", Bioresour. Technol, 148, pp.249~254 (2013)
- Ho SH, "Achieving high lipid productivity of a thermotolerant microalga Desmodesmus sp. F2by optimizing environmental factors and nutrient conditions", Bioresour. Technol, 156, pp.108~116 (2014)
- Rios LF, "Nitrogen Starvation for Lipid Accumulation in the Microalga Species Desmodesmus sp", Appl. Biochem. Biotechnol, 175, pp.469~476 (2015)
- Courchesne NMD, "Enhancement of lipid production using biochemical, genetic and transcription factor engineering approaches", J. Biotechnol, 141, pp.31~41 (2009)
- Hempel N, "Biomass productivity and productivity of fatty acids and amino acids of microalgae strains as key characteristics of suitability for biodiesel production", J. Appl. Phycol, 24, pp.1407~1418 (2012)
- Wu H, "Biodiesel quality and biochemical changes of microalgae Chlorella pyrenoidosa and Scenedesmus obliquus in response to nitrate levels", Bioresour. Technol, 170, pp.421~427 (2014)