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| Two Step Cultivation Mode with “Heterotrophy-stress” for Chlorella Protothecoides Biomass and Lipid Content |
| WANG Gui-lin, GUI Xiao-hua, DENG Wei, ZHAO Zhi-liang, YAO Jie, YAN Yun-jun |
| Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China |
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Abstract A novel cultivation strategy, "heterotrophy - stress" two-step cultivation was developed to solve the problem of asynchronism between biomass and lipid production in Chlorella protothecoides research. The C. protothecoides was first cultivated in optimized heterotrophic medium to achieve high cell density with low lipid content. Then, the algal cells were washed, condensed and transferred to stress medium without nitrogen source in order to accumulate high lipid content. With this strategy, the C. protothecoides biomass in 500ml flask achieved 5.32 g/L dry-weight which was close to the level of traditional heterotrophic cultivation mode, but the lipid content increased from 15.40% to 34.81%, and the algal polysaccharide content of the residue after lipid extraction increased from 9.57% to 18.06%. Furthermore, a 3L fermenter experiment showed a consistent pattern. In nitrogen rich medium, the biomass reached 14.1 g/L dry-weight, lipid content reached 17.16%, and the algal polysaccharide content was 10.16%, while in " heterotrophy - stress" two-step cultivation, the biomass attained 13.2 g/L dry-weight, the lipid attained 40.15%, and the algal polysaccharide content was 24.74%. Therefore, this study indicates that the proposed strategy may provide an effective approach for microalgal biomass production with high lipid content.
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Received: 05 November 2012
Published: 25 March 2013
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| [1] Wijffels R H, Barbosa M J. An outlook on microalgal biofuels. Science, 2010, 329(5993):796-799.
[2] 夏金兰,万民熙,王润民,等. 微藻生物柴油的现状与进展. 中国生物工程杂志, 2009(7): 118-126. Xia J L, Wan M X, Wang Y M, et al. Research progress on biodiesel producing microalgae cultivation. China Biotechnology, 2009(7): 118-126.
[3] Yan D, Lu Y, Chen Y, et al. Waste molasses alone displaces glucose-based medium for microalgal fermentation towards cost-saving biodiesel production. Bioresour Technol, 2011, 102(11): 6487-6493.
[4] Xiong W, Li X F, Xiang J Y, et al. High-density fermentation of microalga Chlorella protothecoides in bioreactor for microbio-diesel production. Appl Microbiol Biotechnol, 2008, 78(1): 29-36.
[5] Doucha J, Lívansky K. Production of high-density Chlorella cult ure grown in fer menters. J Appl Phycol, 2012(24): 35-42.
[6] Xu H, Miao X L, Wu Q Y. High quality biodiesel production from a microalga Chlorella protothecoides by heterotrophic growth in fermenters. J Biotechnol, 2006, 126(4): 499-507.
[7] Gao C F, Zhai Y, Ding Y, et al. Application of sweet sorghum for biodiesel production by heterotrophic microalga Chlorella protothecoides. Appl Energ, 2010, 87(3): 756-761.
[8] Fan J, Huang J, Li Y, et al. Sequential heterotrophy–dilution–photoinduction cultivation for efficient microalgal biomass and lipid production. Bioresour Technol, 2012, 112: 206-211.
[9] Oh S H, Kwon M C, Choi W Y, et al. Long-term outdoor cultivation by perfusing spent medium for biodiesel production from Chlorella minutissima. J Biosci Bioeng, 2010, 110(2): 194-200.
[10] Li Y T, Han D X, Sommerfeld M, et al. Photosynthetic carbon partitioning and lipid production in the oleaginous microalga Pseudochlorococcum sp (Chlorophyceae) under nitrogen-limited conditions. Bioresour Technol, 2011, 102(1): 123-129.
[11] 王金娜,严小军,周成旭,等. 产油微藻的筛选及中性脂动态积累过程的检测. 生物物理学报, 2010(6): 472-480. Wang J N, Yan X J, Zhou C X, et al. Screening of oil-producing microalgae and detecting dynamics of neutral lipid accumulation. Chinese Journal of Biophysics, 2010(6): 472-480.
[12] Elsey D, Jameson D, Raleigh B, et al. Fluorescent measurement of microalgal neutral lipids. J Microbiol Method, 2007, 68(3): 639-642.
[13] 刘四光,李文权,邓永智. 海洋微藻多糖微波提取法研究. 海洋通报, 2007(4): 105-110. Liu S G, Li W Q, Deng Y Z. Study on the microwave extraction of polysaccharides in marinealga. Marine Science Bulletin, 2007(4): 105-110.
[14] 周妍,王凌,孙利芹,等. 5种海洋微藻多糖体外免疫调节活性的筛选. 海洋通报, 2010(2): 194-198. Zhou Y, Wang L, Sun L Q, et al. Immunomodulation activities of polysaccharides in vitro from five microalgae. Marine Science Bulletin, 2010(2): 194-198.
[15] Converti A, Alessandro A C, Erika Y O, et al. Effect of temperature and nitrogen concentration on the growth and lipid content of Nannochlorapsis oculata and Chlorella vulgaris for biodiesel production. Chem Eng Process: Process Intensification, 2009(48): 1146-1151.
[16] Illman A M, Scragg A H, Shales S W. Increase in Chlorella strains calorific values when grown in low nitrogen medium. Enzyme Microb Technol, 2000, 27(8): 631-635.
[17] Evans Ct S A R. C. Regulation of citrateefflux from mitochondria of oleaginous and non-oleaginous yeasts by adenine nucleotides. Eur J Biochem, 1983, 132(3): 609-615.
[18] Botham Pa R C. A biochemical explanation for lipid accumulation in Candida 107 and other oleaginous microorganisms. Gen Microbiol, 1979(114): 361-375.
[19] Orús M I M E M F. Suitability of Chlorella vulgaris UAM 101 for heterotrophic biomass production. Bioresour Technol, 1991, 38(23): 179-184.
[20] Meng X, Yang J, Xu X, et al. Biodiesel production from oleaginous microorganisms. Renew Energ, 2009, 34(1): 1-5. |
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