A comparison on effects of different concentrations of sodium chloride on activeness of anti oxidant enzymes, smolites and photosynthetic pigments in Dunaliella salina

The present study evaluated the effects of concentration of sodium chloride in medium culture on fluctuations of activeness of anti oxidant enzymes (such as catalase, scorbate peroxidase, peroxidase, and superoxide dismutase), fluctuations of smolites contents (such as glycine betaine, and proline) and fluctuations of quantity of pigments. The experimental strain was grown in three treatments with 2.5, 7.5 and 12.5 percent sodium chloride and was subject to evaluation of the target parameters. The strain grown in 7.5 percent treatment showed most growth compared to other treatments. Also greatest values for chlorophyll A (10.3 milligram per gram wet weight of algae), chlorophyll B (0.753 milligram per gram wet weight of algae), and beta-carotene (0.211 milligram per gram wet weight of algae); but an increase in chlorophyll B was seen in other treatments. Results of enzyme evaluations showed that activeness of peroxydase and ascorbic peroxydase increased significantly in the two other sodium chloride treatments (p<0.05). Moreover, glycine betain concentration in optimum condition was more than the other two treatments (P<0.05). In non optimum condition, concentration of proline increased significantly (P<0.05). Growth in 7.5 percent sodium chloride was greatest; it is likely that cells in order to eliminate stress of salinity change components of photosynthetic antennae to increase photo system 2 combined with synthesizing proline and anti oxidative enzyme proteins.