A team of researchers from South Korea has developed a new strategy to efficiently produce fatty acids and biofuels from glucose.
In a study published in the journal Nature Chemical Biology, researchers from Korea Advanced Institute of Science and Technology have shown how glucose and oleaginous microorganisms can be transformed into microbial diesel fuel, through direct fermentative production.
Developed by Professor Sang Yup Lee and his team, the new strain showed very high efficiency in producing fatty acids and biodiesel.
While biodiesel is largely produced through the transesterification of vegetable oils or animal fats, the South Korean team has engineered oleaginous microorganisms, known as Rhodococcus opacus, to produce fatty acids and their derivatives, which can be used as biodiesel, from glucose.
The researchers have previously engineered Escherichia coli to produce short-chain hydrocarbons, which can be used as gasoline (this work was published in the Nature journal in 2013).
However, the production efficiency using E. coli fell short of the levels required for commercialisation, leading the team to instead use Rhodococcus opacus as a host strain in their latest research.
They first optimised the cultivation conditions of Rhodococcus opacus to maximise the accumulation of oil (triacylglycerol), which serves as a precursor for the biosynthesis of fatty acids and their derivatives.
The team then systematically analysed the metabolism of the strain and redesigned it to enable higher levels of fatty acids, as well as two types of fatty acid-derived biodiesel to be produced.
The resulting strains have been recorded as the highest concentrations ever by microbial fermentations, and it is hoped that they will contribute to the future industrialisation of microbial-based biodiesel production.
“This technology creates fatty acids and biodiesel with high efficiency by utilising lignocellulose, one of the most abundant resources on the Earth, without depending on fossil fuels and vegetable or animal oils,” explained Professor Lee. “This will provide new opportunities for oil and petroleum industries, which have long relied on fossil fuels, to turn to sustainable and eco-friendly biotechnologies.”
The research paper, titled ‘Engineering of an oleaginous bacterium for the production of fatty acids and fuels’, was published in Nature Chemical Biology in June.