Rapid neutral lipid accumulation of the alkali-resistant oleaginous Monoraphidium dybowskii LB50 by NaCl induction

• Published in: Bioresource technology 2014-11, Vol.172, p.131-137
• Main Authors: Yang, Haijian, He, Qiaoning, Rong, Junfeng, Xia, Ling, Hu, Chunxiang
• Format: Article
• Language: English
• Subjects: Air; Algae; Alkalies - pharmacology; Biological and medical sciences; Biomass; Cultivation; Freshwaters; Fundamental and applied biological sciences. Psychology; Glycolipids; Light; Lipid Metabolism - drug effects; Lipid Metabolism - radiation effects; Lipids; Lipids - biosynthesis; Microalgae - drug effects; Microalgae - metabolism; Microalgae - radiation effects; Monoraphidium; Monoraphidium dybowskii LB50; NaCl induction; Neutral lipid productivity; Optimization; Outdoor; Phospholipids; Photobioreactors - microbiology; Productivity; Sodium Chloride - pharmacology; Strategy; Temperature
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2014.08.066

•0.25gL−1 urea and 0.1M NaHCO3 are optimal nutritions for M. dybowskii LB50.•Neutral lipid productivity is enhanced by 20gL−1 NaCl.•Induction and cultivation time are shortened at optimum NaCl addition.•Induction efficiency in 140L reactor is the same as that in 5L flasks.•Membrane remodeling contributes to NL accumulation under salt stress. NaCl is an effective inducer of lipid accumulation in freshwater microalgae, but little is known on whether the enhanced lipid components are desired. To address this issue, Monoraphidium dybowskii LB50 from a freshwater habitat was selected, cultivated, and subjected to NaCl induction at different scales outdoors. Results showed that the optimal salt concentration reduced glycolipid (GL) content, as well as enhanced neutral lipid (NL) and phospholipid (PL) contents. Moreover, GL was preferentially converted to NL at 20gL−1 NaCl. Total lipid and NL contents respectively increased to 41.7% and 17.48% in 1d. The highest NL productivity was also achieved at both the 5L (24.13mgL−1d−1) and 140L (13.05mgL−1d−1, 3.43gm−2d−1) scales. These results suggest that NL accumulated effectively and rapidly at different scales, indicating that this strategy has broad application prospects for the scale-up cultivation of oily algae.