초록
<P><B>Abstract</B></P> <P>In this study, <I>Nannochloropsis oceanica</I> CY2 was grown in deep-sea water (DSW)-based medium in 5-L plastic bag-type photobioreactors (PBRs) for the autotrophic production of Eicosapentaenoic acid (EPA, 20:5n-3). EPA production of <I>N. oceanica</I> CY2 was stimulated when it was grown in 100% DSW amended with 1.5 g L<SUP>−1</SUP> NaNO<SUB>3</SUB>, achieving a EPA content of 3.1% and a biomass concentration of 3.3 g L<SUP>−1</SUP>. An outdoor-simulated microalgae cultivation system was also conducted to validate the feasibility of outdoor cultivation of the CY2 strain in plastic bag-type PBRs. Using an inoculum size of 0.6 g/L, the biomass concentration in the PBR culture was 3.5 g L<SUP>−1</SUP>, while the EPA content and productivity reached a maximal level of 4.12% and 7.49 mg L<SUP>−1</SUP> d<SUP>−1</SUP>, respectively. When the PBRs were operated on semi-batch mode, the EPA productivity could further increase to 9.9 mg L<SUP>−1</SUP> d<SUP>−1</SUP> with a stable EPA content of 4.1%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A microalga <I>Nannochloropsis oceanica</I> CY2 shows high potential as an EPA producer. </LI> <LI> Deep-sea water (DSW) was used to stimulate EPA production of <I>N. oceanica</I> CY2. </LI> <LI> Plastic bag-type PBRs were used to grow the microalga on DSW medium in large scale. </LI> <LI> Semi-batch operation is effective in enhancing EPA productivity of <I>N. oceanica</I> CY2. </LI> </UL> </P>