Advertisement

BioEnergy Research

, Volume 8, Issue 4, pp 1824–1830 | Cite as

Rapid Lipid Induction in Chlorella sp. by UV-C Radiation

  • Kalpesh K. Sharma
  • Yan Li
  • Peer M. Schenk
Article

Abstract

Rapid induction of lipid accumulation in microalgae is an important prerequisite towards the use of microalgae as a feedstock for biodiesel production. In this study, we present a novel approach to induce lipids in Chlorella sp. within 24 h by short-term UV-C radiation (UVR) stress at different energy intensities ranging from 0 to 1000 mJ/cm2. Increase in the lipid fluorescence was measured by Nile red staining and fluorescence-activated cell sorting analysis followed by gas chromatography-mass spectrometry. Lipid fluorescence was significantly increased in cultures radiated at or above 250 mJ/cm2 compared to the mock-treated control cultures. Lower dosages at 100 and 250 mJ/cm2 led to a near doubling of total fatty acids, with a significant increase in unsaturated fatty acids and also most saturated fatty acids. This study provides a protocol for rapid lipid induction of microalgal cells by UV-C and the possible impact of UV-C radiation on fatty acid metabolism.

Keywords

Chlorella Lipids Microalgae PUFA UV-C 

Notes

Acknowledgments

We wish to thank the Australian Research Council for financial support.

Supplementary material

12155_2015_9633_MOESM1_ESM.pdf (214 kb)
Online Resource Figure 1 Analysis of the non-polar fraction of TAGs in Chlorella sp. BR2 treated with different UV-C radiation doses (0–1000 mJ/cm2). (PDF 213 kb)
12155_2015_9633_MOESM2_ESM.pdf (162 kb)
Online Resource Figure 2 FACS analysis of Chlorella sp. BR2. Shown are cells without Nile red staining (Unstained Cells) and Nile red-stained with different UV-C dosages ranging from 0 mJ/cm2 (Control) to 1000 mJ/cm2 showing P1 and P2 populations. The Y-axis shows fluorescence intensity at the phycoerythrin excitation wavelength of 575 nm, and the X-axis shows the forward scatter based on cell size. (PDF 161 kb)
12155_2015_9633_MOESM3_ESM.pdf (136 kb)
Online Resource Figure 3 Comparison of different saturated fatty acids present in Chlorella sp. BR2 cultures treated with different doses of UV-C radiation. Values are mean ± SE from three separately grown cultures (n = 3); bars with different letters indicate significant differences (P < 0.05). (PDF 136 kb)
12155_2015_9633_MOESM4_ESM.pdf (144 kb)
Online Resource Figure 4 Comparison of different unsaturated fatty acids present in Chlorella sp. BR2 cultures treated with different doses of UV-C radiation. Values are mean ± SE from three separately grown cultures (n = 3); bars with different letters indicate significant differences (P < 0.05). (PDF 143 kb)
12155_2015_9633_MOESM5_ESM.pdf (54 kb)
Online Resource Figure 5 Growth curve of Chlorella sp. BR2 cells. UV-C treatment was applied during the late exponential growth phase (1.6 × 107 cells/mL). Values are mean ± SE from three separately grown cultures (n = 3). (PDF 53 kb)
12155_2015_9633_MOESM6_ESM.pdf (53 kb)
Online Resource Figure 6 Comparison of total fatty acids present in Chlorella sp. BR2 cells treated with different doses of UV-C radiation. Shown are mean amounts ± SE of total fatty acids in micrograms/cell from three separately grown cultures (n = 3); bars with different letters indicate significant differences (P < 0.05). (PDF 52 kb)

References

  1. 1.
    Schenk PM, Thomas-Hall S, Stephens E, Marx U, Mussgnug J, Posten C, Kruse O, Hankamer B (2008) Second generation biofuels: high-efficiency microalgae for biodiesel production. Bioenergy Res 1(1):20–43CrossRefGoogle Scholar
  2. 2.
    Li Y, Qin JG, Moore RB, Ball AS (2009) Perspectives of marine phytoplankton as a source of nutrition and bioenergy. In: Marine phytoplankton. Nova Science Publishers, IncGoogle Scholar
  3. 3.
    Yongmanitchai W, Ward OP (1991) Screening of algae for potential alternative sources of eicosapentaenoic acid. Phytochemistry 30(9):2963–2967CrossRefGoogle Scholar
  4. 4.
    Rodolfi L, Zittelli GC, Bassi N, Padovani G, Biondi N, Bonini G, Tredici MR (2009) Microalgae for oil: strain selection, induction of lipid synthesis and outdoor mass cultivation in a low-cost photobioreactor. Biotechnol Bioeng 102:100–112CrossRefPubMedGoogle Scholar
  5. 5.
    Huntley M, Redalje D (2007) CO2 mitigation and renewable oil from photosynthetic microbes: a new appraisal. Mitig Adapt Strateg Glob Chang 12(4):573–608CrossRefGoogle Scholar
  6. 6.
    Illman AM, Scragg AH, Shales SW (2000) Increase in Chlorella strains calorific values when grown in low nitrogen medium. Enzym Microb Technol 27(8):631–635CrossRefGoogle Scholar
  7. 7.
    Lv J-M, Cheng L-H, Xu X-H, Zhang L, Chen H-L (2010) Enhanced lipid production of Chlorella vulgaris by adjustment of cultivation conditions. Bioresour Technol 101(17):6797–6804CrossRefPubMedGoogle Scholar
  8. 8.
    Griffiths M, Harrison S (2009) Lipid productivity as a key characteristic for choosing algal species for biodiesel production. J Appl Phycol 21(5):493–507CrossRefGoogle Scholar
  9. 9.
    Liu Z-Y, Wang G-C, Zhou B-C (2008) Effect of iron on growth and lipid accumulation in Chlorella vulgaris. Bioresour Technol 99(11):4717–4722CrossRefPubMedGoogle Scholar
  10. 10.
    Miao X, Wu Q (2006) Biodiesel production from heterotrophic microalgal oil. Bioresour Technol 97(6):841–846CrossRefPubMedGoogle Scholar
  11. 11.
    Miao X, Wu Q (2004) High yield bio-oil production from fast pyrolysis by metabolic controlling of Chlorella protothecoides. J Biotechnol 110(1):85–93CrossRefPubMedGoogle Scholar
  12. 12.
    Xiong W, Li X, Xiang J, Wu Q (2008) High-density fermentation of microalga Chlorella protothecoides in bioreactor for microbio-diesel production. Appl Microbiol Biotechnol 78(1):29–36CrossRefPubMedGoogle Scholar
  13. 13.
    de-Bashan LE, Bashan Y, Moreno M, Lebsky VK, Bustillos JJ (2002) Increased pigment and lipid content, lipid variety, and cell and population size of the microalgae Chlorella spp. when co-immobilized in alginate beads with the microalgae-growth-promoting bacterium Azospirillum brasilense. Can J Microbiol 48:514–521CrossRefPubMedGoogle Scholar
  14. 14.
    Greenwell HC, Laurens LML, Shields RJ, Lovitt RW, Flynn KJ (2009) Placing microalgae on the biofuels priority list: a review of the technological challenges. J Royal Soc Interface rsif20090322Google Scholar
  15. 15.
    Hu Q, Sommerfeld M, Jarvis E, Ghirardi M, Posewitz M, Seibert M, Darzins A (2008) Microalgal triacylglycerols as feedstocks for biofuel production: perspectives and advances. Plant J 54(4):621–639CrossRefPubMedGoogle Scholar
  16. 16.
    Sharma KK, Schuhmann H, Schenk PM (2012) High lipid induction in microalgae for biodiesel production. Energies 5(5):1532–1553CrossRefGoogle Scholar
  17. 17.
    Thompson GA (1996) Lipids and membrane function in green algae. Biochim Biophys Acta 1302(1):17–45CrossRefPubMedGoogle Scholar
  18. 18.
    Guihéneuf F, Fouqueray M, Mimouni V, Ulmann L, Jacquette B, Tremblin G (2010) Effect of UV stress on the fatty acid and lipid class composition in two marine microalgae Pavlova lutheri (Pavlovophyceae) and Odontella aurita (Bacillariophyceae). J Appl Phycol 22(5):629–638CrossRefGoogle Scholar
  19. 19.
    Forján E, Garbayo I, Henriques M, Rocha J, Vega J, Vílchez C (2011) UV-A mediated modulation of photosynthetic efficiency, xanthophyll cycle and fatty acid production of Nannochloropsis. Mar Biotechnol 13(3):366–375CrossRefPubMedGoogle Scholar
  20. 20.
    Guihéneuf F, Mimouni V, Ulmann L, Tremblin G (2009) Combined effects of irradiance level and carbon source on fatty acid and lipid class composition in the microalga Pavlova lutheri commonly used in mariculture. J Exp Mar Biol Ecol 369(2):136–143CrossRefGoogle Scholar
  21. 21.
    Holzinger A, Lütz C (2006) Algae and UV irradiation: effects on ultrastructure and related metabolic functions. Micron 37(3):190–207CrossRefPubMedGoogle Scholar
  22. 22.
    Xue L, Zhang Y, Zhang T, An L, Wang X (2005) Effects of enhanced ultraviolet-B radiation on algae and cyanobacteria. Crit Rev Microbiol 31(2):79–89CrossRefPubMedGoogle Scholar
  23. 23.
    He Y-Y, Häder D-P (2002) UV-B-induced formation of reactive oxygen species and oxidative damage of the cyanobacterium Anabaena sp.: protective effects of ascorbic acid and N-acetyl-cysteine. J Photochem Photobiol B Biol 66(2):115–124CrossRefGoogle Scholar
  24. 24.
    Bhandari R, Sharma P (2011) Photosynthetic and biochemical characterization of pigments and UV-absorbing compounds in Phormidium tenue due to UV-B radiation. J Appl Phycol 23(2):283–292CrossRefGoogle Scholar
  25. 25.
    Wiley PS (2009) Photosynthetic and oxidative stress in the green alga Dunaliella tertiolecta: The effects of UV-B and UV-A radiation. Ph.D., University of New Hampshire, United States - New HampshireGoogle Scholar
  26. 26.
    Sharma K, Li Y, Schenk P (2014) UV-C-mediated lipid induction and settling, a step change towards economical microalgal biodiesel production. Green Chem 16:3539–3548CrossRefGoogle Scholar
  27. 27.
    Lim DK, Garg S, Timmins M, Zhang ES, Thomas-Hall SR, Schuhmann H, Li Y, Schenk PM (2012) Isolation and evaluation of oil-producing microalgae from subtropical coastal and brackish waters. PLoS ONE 7(7), e40751PubMedCentralCrossRefPubMedGoogle Scholar
  28. 28.
    Guillard RR, Ryther JH (1962) Studies of marine planktonic diatoms .1. Cyclotella nana Hustedt, and Detonula confervacea (Cleve) Gran. Can J Microbiol 8(2):229CrossRefPubMedGoogle Scholar
  29. 29.
    Timmins M, Zhou W, Rupprecht J, Lim L, Thomas-Hall SR, Doebbe A, Kruse O, Hankamer B, Marx UC, Smith SM, Schenk PM (2009) The metabolome of Chlamydomonas reinhardtii following induction of anaerobic H2 production by sulfur depletion. J Biol Chem 284(35):23415–23425CrossRefGoogle Scholar
  30. 30.
    Takagi M, Karseno YT (2006) Effect of salt concentration on intracellular accumulation of lipids and triacylglyceride in marine microalgae Dunaliella cells. J Biosci Bioeng 101(3):223–226CrossRefPubMedGoogle Scholar
  31. 31.
    Dring MJ, Makarov V, Schoschina E, Lorenz M, Lüning K (1996) Influence of ultraviolet-radiation on chlorophyll fluorescence and growth in different life-history stages of three species of Laminaria (Phaeophyta). Mar Biol 126(2):183–191CrossRefGoogle Scholar
  32. 32.
    Karentz D, Cleaver JE, Mitchell DL (1991) Cell survival characteristics and molecular responses of antarctic phytoplankton to ultraviolet-B radiation. J Phycol 27(3):326–341CrossRefGoogle Scholar
  33. 33.
    Chen M, Tang H, Ma H, Holland TC, Ng KYS, Salley SO (2011) Effect of nutrients on growth and lipid accumulation in the green algae Dunaliella tertiolecta. Bioresour Technol 102(2):1649–1655CrossRefPubMedGoogle Scholar
  34. 34.
    Rothschild LJ (1999) The influence of UV radiation on protistan evolution. J Eukaryot Microbiol 46(5):548–555CrossRefPubMedGoogle Scholar
  35. 35.
    Cockell CS (2000) The ultraviolet history of the terrestrial planets—implications for biological evolution. Planetary Space Sci 48(2–3):203–214CrossRefGoogle Scholar
  36. 36.
    Cockell CS, Raven JA (2007) Ozone and life on the Archaean Earth. Philos Trans R Soc A Math Phys Eng Sci 365(1856):1889–1901CrossRefGoogle Scholar
  37. 37.
    Gupta R, Bhadauriya P, Chauhan V, Bisen P (2008) Impact of UV-B radiation on thylakoid membrane and fatty acid profile of Spirulina platensis. Curr Microbiol 56(2):156–161CrossRefPubMedGoogle Scholar
  38. 38.
    Lim DK, Sharma K, Garg S, Schenk PM (2010) The race for highly productive microalgae strains. Bio fuels 1(6):835–837Google Scholar
  39. 39.
    Brett M, Müller-Navarra D (1997) The role of highly unsaturated fatty acids in aquatic foodweb processes. Freshw Biol 38(3):483–499CrossRefGoogle Scholar
  40. 40.
    Richard D, Kefi K, Barbe U, Bausero P, Visioli F (2008) Polyunsaturated fatty acids as antioxidants. Pharmacol Res 57(6):451–455CrossRefPubMedGoogle Scholar
  41. 41.
    Chi X, Zhang X, Guan X, Ding L, Li Y, Wang M, Lin H, Qin S (2008) Fatty acid biosynthesis in eukaryotic photosynthetic microalgae: identification of a microsomal delta 12 desaturase in Chlamydomonas reinhardtii. J Microbiol 46(2):189–201CrossRefPubMedGoogle Scholar
  42. 42.
    Bouhamidi R, Prévost V, Nouvelot A (1998) High protection by grape seed proanthocyanidins (GSPC) of polyunsaturated fatty acids against UV-C induced peroxidation. Comptes Rendus de l’Académie des Sci - Series III - Sci de la Vie 321(1):31–38Google Scholar

Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Algae Biotechnology Laboratory, School of Agriculture and Food SciencesThe University of QueenslandBrisbaneAustralia

Personalised recommendations