초록
<P><B>Highlights</B></P><P>► Cu (II) enhances growth and carotenoid accumulation of <I>Coccomyxa onubensis</I>. ► Semicontinuous cultivation in Cu (II)-containing culture media leads to increased productivities of <I>C. onubensis</I>. ► Low pH and presence of Cu (II) determines maximal lutein productivity in cultures of <I>C. onubensis</I>.</P> <P><B>Abstract</B></P><P>The influence of Cu (II) on productivity and accumulation of value carotenoids of a microalga that naturally grows at low pH, <I>Coccomyxa onubensis</I>, was investigated. The presence of Cu (II), added in range between 0.06 and 0.4mM, increases both algal viability and synthesis of carotenoids, mostly lutein and β-carotene. A copper concentration of 0.2mM was found to be as the most appropriate one to enhance productivity and lutein accumulation and was further used in semicontinuous cultures. Unlike acidophile microalgae, <I>C. onubensis</I> showed unusual high growth rates (0.50d<SUP>−1</SUP>) when cultured semicontinuously at 0.2mM Cu (II) and getting an average productivity of 0.42gl<SUP>−1</SUP>d<SUP>−1</SUP>. Lutein content in 0.2mM Cu (II) cultures was roughly 50% higher than that obtained for control cultures. <I>C. onubensis</I> seems to have great potential as lutein producer when compared to known lutein accumulating microalgae. <I>C. onubensis</I> is able to live in highly selective environment, which confers the microalga a competitive advantage over other organisms that cannot survive at such low pH and high concentrations of heavy metals. This might make of <I>C. onubensis</I> a unique alga for large producer in open systems.</P>