Effect of culture condition on the growth, biochemical composition and EPA production of alkaliphilic Nitzschia plea isolated in the Southeast of China
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To overcome the contamination in open pond, microalgal strain selection should focus on species with tolerability to extreme environments. In this study, a native alkaliphilic algae, diatom Nitzschia plea was obtained in Southeast of China, which could tolerate high concentration of NaHCO3 (0.15 mol/L) and high pH (> 10). The effects of initial pH, light intensity and temperature on cell growth, biochemical composition and fatty acid profile of N. plea were investigated. Results indicated its specific growth rate could reach 1.2 day−1, lipid content was in the range 14.6–30.2% of dry weight, eicosapntemacnioc acid (EPA, C20:5) accounted for around 15% of total fatty acids. Alkalic condition benefited for both cell growth and EPA synthesis. Appropriately increasing light intensity and temperature could improve cell growth rate and lipid synthesis, although the proportion of EPA in total fatty acids decreased slightly. The optimal culture condition (pH 9.00, temperature 35.0 °C, light intensity 158.6 µmol/m2s) was suggested for maximum yield of EPA based on the response surface model. The overall biomass productivity and EPA productivity were 0.301 g/L/day and 7.43 mg/L/day, respectively. In conclusion, alkalic environment was helpful for the steady operation of open pond cultivation of N. plea with the characteristics of fast growth rate and high EPA content, which exhibited its commercial value.
KeywordsAlkaliphilic microalgae Eicosapntemacnioc acid Nitzschia plea Response surface
This study was supported by National Key R&D Program of China (2016YF0601005).
- 6.Richmond A, Karg S, Boussiba S (1982) Effects of bicarbonate and carbonate and carbon dioxide on the competition between Chlorella vulgaris and Spriulina platensis. Plant Cell Physiol 23(8):1411–1417Google Scholar
- 15.Stanier RY, Kunisawa R, Mandel M, Cohenbaz G (1971) Purification and properties of unicellular blue–green algae (Order Cchroococcales). Bacteriol Rev 35(2):171Google Scholar
- 18.Lowry OH, Rosebrough NJ, Farr AL, Randall RJ (1951) Protein measurement with the Folin phenol reagent. J Bio Chem 193(1):265–275Google Scholar
- 27.Hosono H, Uemura I, Takumi T, Nagamune T, Yasuda T, Kishimoto M, Nagashima H, Shimomura N, Natori M, Endo I (1994) Effect of culture temperature shift on the cellular sugar accumulation of Chlorella vulgaris SO-26. J Biosci Bioeng 78(3):235–240Google Scholar
- 29.Renuad SM, Zhou HC, Parry DL, Think L-V, Woo KC (1995) Effect of temperature on the growth, total lipid content and fatty acid composition of recently isolated tropical microalgae Isochrysis sp., Nitzschia closterium, Nitzschia paleacea, and commerical species Isochrysis sp.(clone T. ISO). J Appl Phycol 7:595–602CrossRefGoogle Scholar
- 34.Simionato D, Block MA, La Rocca N, Jouhet J, Maréchal E, Finazzi G, Morosinotto T (2013) The Response of Nannochloropsis gaditana to nitrogen starvation includes de novo biosynthesis of triacylglycerols, a decrease of chloroplast galactolipids, and reorganization of the photosynthetic apparatus. Eukaryot Cell 12(5):665–676CrossRefGoogle Scholar