Tiina Paalme1, Liina Pajusalu1 and Marju Robal2
1 Estonian Marine Institute, University of Tartu, Mäealuse 14, 12618 Tallinn, Estonia
2 School of Natural Sciences and Health, Tallinn University, Narva mnt 25, 10120 Tallinn, Estonia
Ceramium tenuicorne (Ceramiales, Rhodophyta) is widely distributed red macroalgal species in the Baltic Sea. The species has lately earned increased attention as a potential source of highly valued bioactive compounds, first for extraction of the red pigment R-phycoerythrin of analytical grade purity, which is commonly used for its fluorescence properties in biochemistry and as a marker in cell studies. As a part of the development of technology suitable for land-based cultivation of C. tenuicorne laboratory experiments to test the effects of light on pigment content and net photosynthetic rate were carried out. The aim of this study was the optimization of cultivation conditions to obtain biomass which quality is suitable for the extraction of the pigment (high content of R-phycoerythrin) and provide high growth rate of the species. The results showed that at low incubation irradiances (PAR 20-30 µmol m-2 s-1) the R-phycoerythrin contents of C. tenuicorne were significantly, up to three times higher compared to higher irradiances (PAR >90 µmol m-2 s-1). The opposite effect of irradiance was revealed for net photosynthesis of C. tenuicorne, i.e., over two times lower net photosynthesis rates at above mentioned low light conditions compared to higher incubation irradiance were obtained. Meanwhile, the use of blue light instead of white in experiments performed at higher irradiances enhanced remarkable the R-phycoerythrin contents of C. tenuicorne but reduced the net photosynthetic rates to certain extent. Thus, further optimization of cultivation conditions will be needed to refine the biomass and increase the economic potential of C. tenuicorne.