초록
<P><B>Abstract</B></P> <P>Microalgal starch is considered a promising feedstock for bioethanol production. The biomass and starch accumulation in the marine microalga <I>Tetraselmis subcordiformis</I> were characterized under different salinities in response to nitrogen repletion (+N) or depletion (−N) at high irradiance (HI) or low irradiance (LI). Under favorable nutritional conditions (HI+N), biomass accumulation was seldom affected under 20% normal salinity, though starch accumulation were somewhat reduced. Increased salinity impaired overall biomass and starch accumulation, though it led to a temporary starch accumulation at initial cultivation phase. Under nitrogen deprivation, decreased salinity strengthened biomass and starch accumulation regardless of irradiance. The highest starch content of 58.2% dry weight and starch productivity of 0.62gL<SUP>−1</SUP> d<SUP>−1</SUP> were obtained under HI−N with 20% normal salinity. Decreased salinity combined with −N generated moderate stress to facilitate starch accumulation. Salinity manipulation can be effectively applied for enhanced starch production in marine microalgae.</P> <P><B>Highlights</B></P> <P> <UL> <LI> High salinity impaired biomass and starch production in <I>Tetraselmis subcordiformis</I>. </LI> <LI> Under HI+N hyper-osmotic stress caused a temporary but limited starch accumulation. </LI> <LI> Under HI−N and LI−N low salinity strengthened biomass and starch accumulation. </LI> <LI> Decreased salinity under −N caused moderate stress to facilitate starch production. </LI> <LI> Salinity regulation can be used to enhance starch production in marine microalgae. </LI> </UL> </P>