APPLICATIONS OF TECHNOLOGY:
- Cold weather anticlouding additive for diesel fuels
- Diesel or jet fuel alternative
- Platform for advanced biosynthetic fuels development
- Derived Cetane Number (DCN) comparable to No. 2 diesel
- Beneficial cold fuel properties
- Enhanced yield through engineered microbial synthesis
Researchers at JBEI have metabolically engineered both bacteria (E. coli) and yeast (S. cerevisiae) to produce a chemical precursor, bisabolene, that readily converts to bisabolane when saturated with hydrogen gas under pressure. With continuous yield improvements, biosynthetic bisabolane could become a renewable diesel fuel alternative offering comparable energy density and superior cold weather performance to standard D2 diesel fuel.
Although bisabolane had not previously been considered as a biofuel, testing revealed that its performance rating, or Derived Cetane Number (DCN), was 41.9, which is within the 40-55 range of standard diesel fuel. In addition, the analysis showed its “cloud point,” an important marker for cold weather performance, was -78°C, better than diesel’s -35°C, and vastly superior to commercial biodiesel’s -3°C. In sufficient quantities, bisabolane could initially serve as a cold weather additive to diesel and biodiesel formulations and, with higher yields, could substitute for these fuels. (In order to acquire enough material for cetane testing, the JBEI researchers isolated bisabolane from commercially available mixtures of the precursor chemical, bisabolene.)
The JBEI team also developed a screening process to identify plant genes involved in the natural production of the precursor chemical, bisabolene, which is produced in small quantities by spruce and fir trees. Using synthetic biology techniques, JBEI scientists inserted a gene from the Grand Fir tree into E. coli bacteria, as well as in a yeast strain widely used for fermentation of ethanol. With further genetic adjustments designed to optimize the production of bisabolene, the yield of that chemical from E. coli has been increased tenfold. Berkeley Lab scientists have thus identified an organic chemical with enormous potential as a diesel oil substitute and developed a robust synthetic biology platform to produce it — and future engineered biofuels — microbially.
DEVELOPMENT STAGE: Bench scale prototype.
STATUS: Published PCT Patent Application, WO/2012/064740 available at wipo.int. Available for licensing or collaborative research.
FOR MORE INFORMATION:
Peralta-Yahya, P.P., Ouellet, M., Chan, R., Mukhopadhyay, A., Keasling, J. D., Lee, T. S. “Identification and microbial production of a terpene-based advanced biofuel,” Nature Communications, Sept. 27, 2011.
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REFERENCE NUMBER: EIB-2837