초록
<P><B>Background</B></P><P>Microbial lipid production using renewable feedstock shows great promise for the biodiesel industry.</P><P><B>Results</B></P><P>In this study, the ability of a lipid-engineered <I>Yarrowia lipolytica</I> strain JMY4086 to produce lipids using molasses and crude glycerol under different oxygenation conditions and at different inoculum densities was evaluated in fed-batch cultures. The greatest lipid content, 31% of CDW, was obtained using a low-density inoculum, a constant agitation rate of 800 rpm, and an oxygenation rate of 1.5 L/min. When the strain was cultured for 450 h in a chemostat containing a nitrogen-limited medium (dilution rate of 0.01 h<SUP>−1</SUP>; 250 g/L crude glycerol), volumetric lipid productivity was 0.43 g/L/h and biomass yield was 60 g CDW/L. The coefficient of lipid yield to glycerol consumption (<I>Y</I><SUB><I>L</I>/gly</SUB>) and the coefficient of lipid yield to biomass yield (<I>Y</I><SUB><I>L</I>/<I>X</I></SUB>) were equal to 0.1 and 0.4, respectively.</P><P><B>Conclusions</B></P><P>These results indicate that lipids may be produced using renewable feedstock, thus providing a means of decreasing the cost of biodiesel production. Furthermore, using molasses for biomass production and recycling glycerol from the biodiesel industry should allow biolipids to be sustainably produced.</P>