Lipid production for second generation biodiesel by the oleaginous yeast Rhodotorula graminis

The increasing cost of vegetable oils is turning the use of microbial lipids into a competitive alternative for the production of biodiesel fuel. The oleaginous yeast Rhodotorula graminis is able to use a broad range of carbon sources for lipid production, and is able to resist some of the inhibitors commonly released during hydrolysis of lignocellulosic materials. Using undetoxified corn stover hydrolysate as substrate, the yeast achieved a lipid productivity and lipid content of 0.21 g/L/h and 34%w/w, respectively. The corresponding results with crude glycerol as carbon source were 0.15 g/L/h and 54%w/w, respectively. Therefore, R. graminis appears to be a suitable candidate for fermentation processes involving renewable resources.