Simultaneous production of triacylglycerol and high-value carotenoids by the astaxanthin-producing oleaginous green microalga Chlorella zofingiensis

Jin Liu; Xuemei Mao; Wenguang Zhou; Michael T Guarnieri

doi:10.1016/j.biortech.2016.04.112

Simultaneous production of triacylglycerol and high-value carotenoids by the astaxanthin-producing oleaginous green microalga Chlorella zofingiensis

Bioresour Technol. 2016 Aug:214:319-327. doi: 10.1016/j.biortech.2016.04.112. Epub 2016 Apr 26.

Authors

Jin Liu¹, Xuemei Mao², Wenguang Zhou³, Michael T Guarnieri⁴

Affiliations

¹ Institute for Food and Bioresource Engineering and Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing 100871, China. Electronic address: gjinliu@pku.edu.cn.
² Institute for Food and Bioresource Engineering and Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing 100871, China.
³ School of Resources, Environmental & Chemical Engineering and MOE Biomass Engineering Research Center, Nanchang University, Nanchang, China; Center for Biorefining, Bioproducts and Biosystems Engineering Department, University of Minnesota, Saint Paul, MN 55108, USA.
⁴ National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401, USA.

PMID: 27152772
DOI: 10.1016/j.biortech.2016.04.112

Abstract

The production of lipids and astaxanthin, a high-value carotenoid, by Chlorella zofingiensis was investigated under different culture conditions. Comparative analysis revealed a good correlation between triacylglycerol (TAG) and astaxanthin accumulation in C. zofingiensis. Stress conditions promoted cell size and weight and induced the accumulation of neutral lipids, especially TAG and astaxanthin, with a concomitant decrease in membrane lipids. The highest contents of TAG and astaxanthin achieved were 387 and 4.89mgg(-1) dry weight, respectively. A semi-continuous culture strategy was developed to optimize the TAG and astaxanthin productivities, which reached 297 and 3.3mgL(-1)day(-1), respectively. Additionally, astaxanthin accumulation was enhanced by inhibiting de novo fatty acid biosynthesis. In summary, our study represents a pioneering work of utilizing Chlorella for the integrated production of lipids and high-value products and C. zofingiensis has great potential to be a promising production strain and serve as an emerging oleaginous model alga.

Keywords: Astaxanthin; Biofuels; Chlorella zofingiensis; Integrated production; Stress conditions; Triacylglycerol.

MeSH terms

Autotrophic Processes
Biomass
Biotechnology / methods*
Carotenoids / metabolism*
Cerulenin / metabolism
Chlorella / growth & development
Chlorella / metabolism*
Fatty Acids / biosynthesis
Lipids / chemistry*
Microalgae / growth & development
Microalgae / metabolism*
Phototrophic Processes
Stress, Physiological
Triglycerides / metabolism*
Xanthophylls / biosynthesis

Substances

Fatty Acids
Lipids
Triglycerides
Xanthophylls
Cerulenin
Carotenoids
astaxanthine