tailieunhanh - High Lipid Induction in Microalgae for Biodiesel Production

In this paper writing: Lipids in Microalgae, Methods of Lipid Induction, Genetic Engineering of Microalgae to Increase Lipid Production | Energies 2012, 5, 1532-1553; doi: OPEN ACCESS energies ISSN 1996-1073 Article High Lipid Induction in Microalgae for Biodiesel Production Kalpesh K. Sharma, Holger Schuhmann and Peer M. Schenk * Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; E-Mails: (.); (.) * Author to whom correspondence should be addressed; E-Mail: ; Tel.: +61-7-3365-8817; Fax: +61-7-3365-1699. Received: 30 March 2012; in revised form: 3 May 2012 / Accepted: 8 May 2012 / Published: 18 May 2012 Abstract: Oil-accumulating microalgae have the potential to enable large-scale biodiesel production without competing for arable land or biodiverse natural landscapes. High lipid productivity of dominant, fast-growing algae is a major prerequisite for commercial production of microalgal oil-derived biodiesel. However, under optimal growth conditions, large amounts of algal biomass are produced, but with relatively low lipid contents, while species with high lipid contents are typically slow growing. Major advances in this area can be made through the induction of lipid biosynthesis, ., by environmental stresses. Lipids, in the form of triacylglycerides typically provide a storage function in the cell that enables microalgae to endure adverse environmental conditions. Essentially algal biomass and triacylglycerides compete for photosynthetic assimilate and a reprogramming of physiological pathways is required to stimulate lipid biosynthesis. There has been a wide range of studies carried out to identify and develop efficient lipid induction techniques in microalgae such as nutrients stress (., nitrogen and/or phosphorus starvation), osmotic stress, radiation, pH, temperature, heavy metals and other chemicals. In addition, several genetic strategies for increased triacylglycerides