초록
<P><B>Abstract</B></P><P><B>Aims</B></P><P>To screen yeasts in relation to the potential to produce single cell oil (SCO) from biodiesel‐derived glycerol and to enhance SCO production in <I>Lipomyces starkeyi</I> and <I>Rhodosporidium toruloides</I> yeasts.</P><P><B>Methods and Results</B></P><P><I>Yarrowia lipolytica</I>,<I> Cryptococcus curvatus</I>,<I> R.？toruloides</I> and <I>L.？starkeyi</I> were grown in nitrogen‐limited flask cultures. <I>Yarrowia lipolytica</I> strains produced citric acid and mannitol. <I>Lipomyces？starkeyi </I>DSM 70296 and <I>R.？toruloides </I>NRRL Y‐27012 showed potential for SCO production, and were cultivated at increasing the initial glycerol concentrations with the initial nitrogen concentration remaining constant. Significant biomass and SCO production were reported even in cultures with high initial glycerol concentrations (i.e. 180？g？l<SUP>−1</SUP>). Lipid quantities of <I>c</I>. 12？g？l<SUP>−1</SUP> (lipid in dry cell weight 35–40%) were obtained for both <I>L.？starkeyi</I> and <I>R.？toruloides</I>, quite high values compared with literature values for oleaginous micro‐organisms growing on glycerol. However, these strains exhibited different kinetic profiles in the synthesis of intracellular polysaccharides. <I>Lipomyces？starkeyi</I> produced a significant quantity of polysaccharides (<I>c</I>. 7？g？l<SUP>−1</SUP>). The yeast lipids contained mainly oleic and palmitic and to a lesser extent linoleic and stearic acids.</P><P><B>Conclusions</B></P><P><I>Lipomyces starkeyi</I> and <I>R.？toruloides</I> are potential SCO producers from crude glycerol.</P><P><B>Significance and Impact of the Study</B></P><P>Very scarce numbers of reports have indicated the production of SCO by <I>L.？starkeyi</I> and <I>R.？toruloides</I> growing on glycerol. We report here that these yeasts are able efficiently to convert raw glycerol into SCO, while <I>L.？starkeyi</I> also synthesizes intracellular polysaccharides in marked quantities.</P>