Exogenous l-proline improved Rhodosporidium toruloides lipid production on crude glycerol

Biotechnology for Biofuels

Qitian Huang¹  Zongbao Kent Zhao¹  Qian Wang¹  Xue Yu¹  Rasool Kamal²  Yuxue Liu²  Qiang Li² 

[1] Laboratory of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, 116023, Dalian, People’s Republic of China;Dalian Key Laboratory of Energy Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, 116023, Dalian, People’s Republic of China;Laboratory of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, 116023, Dalian, People’s Republic of China;University of Chinese Academy of Sciences, 100049, Beijing, People’s Republic of China;

关键词: Anti-stress agent;    Crude glycerol;    Microbial lipids;    Rhodosporidium toruloides;    Two- stage culture;   

DOI  :  10.1186/s13068-020-01798-6

来源: Springer

【 摘 要 】

BackgroundCrude glycerol as a promising feedstock for microbial lipid production contains several impurities that make it toxic stress inducer at high amount. Under stress conditions, microorganisms can accumulate l-proline as a safeguard. Herein, l-proline was assessed as an anti-stress agent in crude glycerol media.ResultsCrude glycerol was converted to microbial lipids by the oleaginous yeast Rhodosporidium toruloides CGMCC 2.1389 in a two-staged culture mode. The media was supplied with exogenous l-proline to improve lipid production efficiency in high crude glycerol stress. An optimal amount of 0.5 g/L l-proline increased lipid titer and lipid yield by 34% and 28%, respectively. The lipid titer of 12.2 g/L and lipid content of 64.5% with a highest lipid yield of 0.26 g/g were achieved with l-proline addition, which were far higher than those of the control, i.e., lipid titer of 9.1 g/L, lipid content of 58% and lipid yield of 0.21 g/g. Similarly, l-proline also improved cell growth and glycerol consumption. Moreover, fatty acid compositional profiles of the lipid products was found suitable as a potential feedstock for biodiesel production.ConclusionOur study suggested that exogenous l-proline improved cell growth and lipid production on crude glycerol by R. toruloides. The fact that higher lipid yield as well as glycerol consumption indicated that l-proline might act as a potential anti-stress agent for the oleaginous yeast strain.

【 授权许可】

CC BY