Application of metabolic controls for the maximization of lipid production in semicontinuous fermentation
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139,, Department of Forensic Science and Technology, Zhejiang Police College, Hangzhou 310053, China
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139,
We report that acetic acid can be generated through syngas fermentation, lignocellulosic biomass degradation, and organic waste anaerobic digestion. Microbial conversion of acetate into triacylglycerols for biofuel production has many advantages, including low-cost or even negative-cost feedstock and environmental benefits. The main issue stems from the dilute nature of acetate produced in such systems, which is costly to be processed on an industrial scale. To tackle this problem, we established an efficient bioprocess for converting dilute acetate into lipids, using the oleaginous yeast Yarrowia lipolytica in a semicontinuous system. The implemented design used low-strength acetic acid in both salt and acid forms as carbon substrate and a cross-filtration module for cell recycling. Feed controls for acetic acid and nitrogen based on metabolic models and online measurement of the respiratory quotient were used. The optimized process was able to sustain high-density cell culture using acetic acid of only 3% and achieved a lipid titer, yield, and productivity of 115 g/L, 0.16 g/g, and 0.8 g∙L-1∙h-1, respectively. No carbon substrate was detected in the effluent stream, indicating complete utilization of acetate. In conclusion, these results represent a more than twofold increase in lipid production metrics compared with the current best-performing results using concentrated acetic acid as carbon feed.
- Research Organization:
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
- Sponsoring Organization:
- USDOE
- Grant/Contract Number:
- SC0008744
- OSTI ID:
- 1367775
- Alternate ID(s):
- OSTI ID: 1465958
- Journal Information:
- Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Vol. 114 Journal Issue: 27; ISSN 0027-8424
- Publisher:
- Proceedings of the National Academy of SciencesCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Similar Records
Functional overexpression and characterization of lipogenesis-related genes in the oleaginous yeast Yarrowia lipolytica
Engineering oxidative stress defense pathways to build a robust lipid production platform in Yarrowia lipolytica