Exploring the biological potential of halophilic microalgea isolated from İzmir Camalti saltern

Microalgae, with their fast growth rates, wide environmental tolerance of some species and with their biochemical composition, have the potential to be used in various biotechnological fields such as food, feed, medicine and biofuels. Therefore, in this thesis study, halophilic microalgae isolated from İzmir Çamaltı Saltern were genetically, physiologically and biochemically characterized to determine their biotechnological potential. Phylogenetic analysis based on rRNA large subunit genes (LSU) clustered 11 of 17 Dunaliella strains with D. salina and 2 were similar to D. viridis. Four strains could not be assigned to a species. On the other hand, rRNA LSU genes with high similarity to those of halophilic Tetraselmis sp. and Cryptophyceae were absent in gene databases. Six genetically different Dunaliella strains were grown in low (65 µmol.foton.m-2.s-1) and high light (650 µmol.foton.m-2.s-1) conditions to compare their growth and pigment production properties. Highest biomasses were observed in low and high light cultures of D. viridis AQUAMEB-2 and high light culture of D. salina AQUAMEB-21. Highest total carotenoids were observed in high light cultures of D. salina. In these D. salina strains 3‰ to 5‰ of algal dry weight were beta carotene according to high pressure liquid chromatography (HPLC) results. Total protein concentrations ranged between 60 mg.g-1 and 180 mg.g-1, total carbohydrate concentrations ranged between 60 mg.g-1 and 250 mg.g-1 and total fatty acid concentrations ranged between 12 mg.g-1 and 40 mg.g-1 per dry weight of the microalgae strains used in the thesis. Eicosapentaenoic acid (EPA) content of Cryptophyceae AQUAMEB-1 and Tetraselmis sp. AQUAMEB-22 were 1.4 mg.g-1 ve 0.8 mg.g-1,respectively, of the algal dry weight. Docosahexaenoic acid (DHA) was only observed in Cryptophyceae AQUAMEB-1 with 0.5 mg.g-1 algal dry weight.