physiological and biochemical responses of dinoflagellate symbiodinium sp. to the different light intensities

Symbiotic dinoflagellates create valuablebioactive compounds such as carotenoidsand lipids, which are used in various industrialfields. however, a small amount of theirbiomass can be produced by using the suspension-based closed photobioreactors. thepresent study tried to obtain high lipid andtotal carotenoid contents from symbiodiniumsp. by creating optimal light intensityconditions using a twin-layer photobioreactor.in this regard, growth rate, biomass,chlorophyll a concentration, and total carotenoidand lipid contents were examinedat the light intensities of 50, 100, and 250μmol.m−2s−1 for 16 days. based on the results,biomass productivities ranged from35.7 to 72.0 g.m-2 at 50 to 250 μmol photonsm−2s−1, respectively. in addition, the highestlinear growth rates were 2.03, 3.27, and 5.85g.m−2d−1 at the light intensity of 50, 100,and 250 μmol.m−2s−1 between 12-16 days,respectively. further, the maximum amountof total carotenoids, chlorophyll a, and totallipid was attained 0.85 and 0.96 g.m^-2, and27.77% at the light intensity of 250 μmol.m^−2s^−1, respectively. the results representedthat the immobilization of algal cells in thephotobioreactor biofilm resulted in producinghigh biomass, total carotenoids, and lipids.