Improvement of Nutritional Values of TWO Dunaliella (Green Microalgae) Species, by Changing in Medium Factors

Unicellular algae as phytoplankton are the important, effective and cheap sources in larvae and aquatic organisms feeding. In this research, assessment of growth rate, pigments contents, total sugar and protein in two species; Dunaliella salina and D. bardawil were studied in three nutrient mediums; Ramaraj (R), Johnson (J) and Shaish (S), during 24days. øFor all mediums, cells growth rate in 1M NaCl was higher than that in 2M and about two times in D. salina compared to that in D. bardawil. The effect of medium kind on cell division, almost observed with the highest in J, S and R, respectively. In 1M, the highest specific growth rate of alga was observed at S and J and in 2M, it was occurred at J, during 8 days. The volume of D. bardawil cells was two times more than D. salina cells and the highest was observed at 2M and S for both species. The changes in fresh and dry weights showed an ascending pattern along with the time, especially in S and J, which was higher at S. In 1M D. bardawil, the highest amount of total carotenoid on the basis of per ml and per dry weights, was observed in S and R mediums, respectively. The changes in beta carotene content by salt concentrations treatments and kind of medium was similar to total carotenoid. The highest amount of total chlorophyll per ml in S and J mediums and the highest amount of this index per dry weight was observed by R treatment. The highest effect for protein increment was related to J which was different from the higher induction effect of R in total sugar production. Totally, these findings suggest the significant effect of medium kind and salt concentration on the increment of nutritional substances in salt water unicellular alga, in addition to the species kind.