Isolation, cultivation and biochemical characterization of the symbiotic dinoflagellate, Symbiodinium sp., from the sea anemone, Stichodactyla haddoni (Saville-Kent, 1893), from the Strait of Hormuz

In the present work, extraction of an endosymbiont from a host of Stichodactyla haddoni collected from the coast of Hormuz Island (the Strait of Hormuz) and afterwards identification, determination of the optimal cultivation conditions and then finding out the parameters and how they affect its bioactive compounds were conducted. The sequence of ITS2 region from the endosymbiont of S. haddoni clustered with 17 sequences representing clade C. The sequence was deposited to the GenBank under accession number MT448855. The study results showed that ASP12 medium and a temperature of 23°C were optimal to cultivate Symbiodinium sp. outside its host. Under these conditions, the highest cell density was 12×105 cell ml-1 and the maximal amount of chlorophyll-a and peridinin were 22.81 and 47.86 mgL-1, respectively. Further cultivation of the obtained strain in a Twin-Layer photobioreactor at light intensities of 50, 100 and 250 μmol photons m-2 s-1 for 16 days demonstrated that the biomass content was observed to be 35.72, 54.77 and 57.12 g m-2 at 50, 100 and 250 µmol photons m-2 s-1; the peridinin content was 0.26, 0.63 and 0.79 g m-2, respectively; total lipid content was 19.5 and 27.77% of dry weight at 50 and 250 µmol photons m-2 s-1.