Optimizing the lipid profile, to produce either a palm oil or biodiesel substitute, by manipulation of the culture conditions for Rhodotorula glutinis

Background: Lipids are an increasingly important chemical feedstock for the manufacture of biofuels, bioplastics, care products and as a food source. Developing sustainable sources of lipids, derived from oleaginous microbes, is therefore a key scientific challenge. Methodology: Design of Experiments was used to optimize the lipid production and lipid profile. Results: Here we successfully apply Design of Experiments to optimize the lipid profile in Rhodotorula glutinis to tailor the fatty acid profile. A high culture temperature and high nitrogen ratio yielded a mainly monounsaturated oil, while low temperatures and high glucose loadings gave a more saturated profile. Conclusions: On transesterification, the oil high in monounsaturated esters yielded biodiesel with fuel properties akin to rapeseed methyl ester, whereas the oil high in saturates was found to be suitable as a substitute for palm oil.