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Updated: Oct 24, 2025
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Synthesis of Esters Via a Greener Steglich Esterification in Acetonitrile
Published on: October 30, 2018
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Microbial synthesis of wax esters.
Ya-Hue Valerie Soong1, Le Zhao2, Na Liu1
1Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA.
Metabolic Engineering
|August 15, 2021
Summary
Engineered yeast and bacteria now produce high yields of valuable wax esters (WE) using waste cooking oil. This breakthrough in microbial biosynthesis offers a sustainable and cost-effective alternative to traditional chemical synthesis for industrial applications.
Area of Science:
- Biotechnology
- Metabolic Engineering
- Industrial Microbiology
Background:
- Wax esters (WE) are high-value industrial molecules with limited natural resources.
- Current production relies on chemical synthesis from expensive precursors.
- Developing efficient microbial cell factories is crucial for cost-effective biomanufacturing.
Purpose of the Study:
- To engineer microbial hosts, Yarrowia lipolytica and Escherichia coli, for high-level wax ester production.
- To optimize metabolic pathways and expression systems for enhanced WE biosynthesis.
- To evaluate the use of low-cost, sustainable feedstocks for WE production.
Main Methods:
- Investigated key genes (fatty acyl-CoA reductases, wax ester synthase) and optimized expression systems in Y. lipolytica.
- Compared various carbon sources (glucose, free fatty acid, soybean oil, waste cooking oil) for WE production efficiency.
- Engineered E. coli BL21(DE3) for improved WE production rates, optimizing substrate feeding strategies.
Main Results:
- Engineered Y. lipolytica produced 7.6 g/L of WE from waste cooking oil with a yield of 0.31 g/g, constituting 57% of dry cell weight.
- Using waste cooking oil increased WE production by 60-fold compared to glucose.
- Engineered E. coli produced 3.7-4.0 g/L of WE within 40 hours in a 1-L bioreactor.
- Predominant WE produced were unsaturated C36, C34, and C32.
Conclusions:
- Successfully engineered Y. lipolytica and E. coli for unprecedented levels of wax ester production.
- Demonstrated the efficacy of using waste cooking oil as a sustainable feedstock for microbial WE biosynthesis.
- This work establishes a foundation for large-scale, cost-effective biomanufacturing of wax esters.
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