초록
<P><I>Yarrowia lipolytica</I>, a well-known oleaginous strain for single cell oil (SCO) production was grown in nitrogen-limited flask cultures. The effect of increasing the initial crude glycerol and nitrogen concentration was studied along the fermentation process. Significant biomass and SCO production was reported with a high initial glycerol concentration of 89 g L<SUP>−1</SUP>and 0.54 g NH4OH per L during 6 h. Optimized culture conditions were tested using a 5 L fermenter during two-stage cultivation with a dissolved oxygen shift from 60% to 30% of dissolved oxygen corresponding to 50-80 h<SUP>−1</SUP>. Lipid concentration of 13.6 ± 0.8 g L<SUP>−1</SUP>and lipid content 52.7 ± 1.2% (w/w of dry biomass) was obtained which is higher compared with literature values for<I>Yarrowia</I>species grown on crude glycerol based media. The yeast lipids contained mainly oleic, palmitic, linoleic and stearic acids which could serve as perfect precursors for the synthesis of biodiesel.</P>