초록
<P><B>Abstract</B></P> <P>In this study, the effects of nitrogen and phosphorus supply on biodiesel production from <I>Scenedesmus obliquus</I> with glucose as the carbon source were investigated. It was found that sufficient phosphorus could further improve biodiesel production under nitrogen starvation. <I>S. obliquus</I> was cultivated in soybean processing wastewater. The removal efficiencies of carbon oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) after 8-day cultivation were 72%, 95%, and 54%, respectively. Moreover, the fatty acid productivity after eight-day cultivation reached as high as 99.3 mg·L<SUP>−1</SUP>·d<SUP>−1</SUP>, which was 1.15 times higher than the highest efficiency using a glucose culture. This result was due to two naturally-formed stages occurring with sufficient phosphorus: nitrogen sufficiency stage for biomass and nitrogen starvation stage for lipid accumulation. It verified the conclusion of the roles of nitrogen and phosphorus obtained in the glucose culture and provided an economic and environmentally friendly choice for biodiesel production with efficient soybean wastewater treatment.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Sufficient P further improves biodiesel production under N starvation in glucose. </LI> <LI> Soybean processing wastewater (SPW) is suitable for applying N and P regulation. </LI> <LI> N-sufficient stage (stage 1) and N-starvation stage (stage 2) are naturally formed. </LI> <LI> <I>S. obliquus</I> grows rapidly in stage 1 and accumulates lipids quickly in stage 2. </LI> <LI> High fatty acids productivity in SPW verifies N and P regulation in glucose. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>