CAROTENOIDS ACCUMULATION BY DUNALIELLA TERTIOLECTA (LAKE URMIA ISOLATE) AND DUNALIELLA SALINA (CCAP 19/18 & WT) UNDER STRESS CONDITIONS

Carotenoids are widely used in nutraceutical, additives and cosmetics as colorants and antioxidants. Dunaliella is the main natural source which accumulates massive amount of carotenoids. This study examines the effect of different concentrations of NaCl (0.3M to 2M) and light intensities of 50 and 150 μmol/m2s on total carotenoids accumulated by Dunaliella tertiolecta (DCCBC26), from Urmia lake (North West of Iran) compared to those obtained from Dunaliella salina CCAP 19/18 and also the wild type Dunaliella salina WT strains. In all microalgaes production of carotenoids were triggered by increase in light intensities. Changes of intensity from 50 μmol/m2s to 150 μmol/m2s led to 2.4, 2.1 and 1.4 folds of carotenoids production by D. salina CCAP, D. salina WT and D. tertiolecta respectively. In both salina strains carotenoids production improved with higher salinity picking at salt concentration of 2M, while D. tertiolecta showed optimum carotenoids production at 0.7M.