Oleochemicals with microbial platform

Oleochemicals are chemicals made from lipids. They are used e.g. in production of soaps, detergents, lubricants, solvents, biodiesel and bioplastics. In addition to plant and animal fats oleochemicals can be produced biotechnically with microbes.  Microbial triacylglycerides can be used as raw material in biodiesel production, and diacids synthesised by microbes find applications in production of bioplastics.

We have enhanced the production of lipids (triacylglycerol) in oleaginous yeast and filamentous fungi by genetic engineering. One to four exogenous genes were expressed to enhance triacylglycerol production, especially the yield per carbon consumed. At the same time, a metabolic pathway which did not exist in these species was established. The genetically modified strains were cultivated in bioreactors with glucose or xylose as carbon source. With glucose (xylose) as carbon source, the genetically modified yeast produced up to 25% (19%) more triacylglycerol (g/l) with 24% (12%) higher yield per used glucose (xylose) than the control strain, which itself already had good triacylglycerol production. The modified filamentous fungus produced up to 9% (18%) more triacylglycerol with 19% (7%) higher yield per used glucose (xylose) than the control strain.

We have also genetically modified a yeast strain to produce diacids from fatty acids.  The omega oxidation of the yeast strain was enhanced and degradation of fatty acids and diacids was blocked. The modified strains showed enhanced production of C9:0 and C18:1 diacids.