초록
<P><B>Abstract</B></P> <P>The green microalga <I>Chromochloris zofingiensis</I> is a promising producer of natural astaxanthin. In the present study, <I>C. zofingiensis</I> was first cultivated in shake flasks under low light irradiation and then subjected to continuous high light irradiation, which effectively promoted astaxanthin production. In addition, a microplate-based culture system in concert with high light irradiation from blue light and white light above 150μmolm<SUP>−2</SUP> s<SUP>−1</SUP> was constructed and applied to improve astaxanthin production. Blue light exerted more positive influences on astaxanthin accumulation, but when the light intensity was increased to 300μmolm<SUP>−2</SUP> s<SUP>−1</SUP>, astaxanthin biosynthesis was substantially inhibited. Conversely, in a nitrogen-deprived culture under white light, the highest astaxanthin content for <I>C. zofingiensis</I>, 7.1mg/g, was obtained. The highest astaxanthin yield achieved was 38.9mg/L in a culture with 0.1g/L nitrate under the same culture conditions. This study demonstrates that <I>C. zofingiensis</I> has great potential for natural astaxanthin production.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Different light supplies influenced nutrient consumption of <I>C. zofingiensis.</I> </LI> <LI> The algal cell density was highly correlated to the uptake of carbon and phosphorus. </LI> <LI> High content (7.1mg/g) and yield (38.9mg/L) of astaxanthin were obtained. </LI> <LI> Blue light improved the astaxanthin/canthaxanthin ratio compared to white light. </LI> <LI> Excess blue light inhibited cell growth and astaxanthin accumulation. </LI> </UL> </P>