the effect of instantaneous and slow-release salt stress methods on beta-carotene production within dunaliella salina cells

The main concept of the present study is taken from the growth pattern of dunaliella salina (green unicellular eukaryote microalgae) in urmia lake which is the second biggest saline lake in the world. in this study, different models of salt stress, including instantaneous (1 and 2 m) and consecutive slow-release salt stresses (0.5 m) were tested, and the amount of beta-carotene for each test was evaluated. according to the results, the highest amount of beta-carotene was obtained by the slow release method of salt injection with the amount of 9.01 μg of beta-carotene per mg of the dry weight of microalgae. the largest amount of beta-carotene production in 1 and 2 m instantaneous salt stresses method were recorded as 4.35 and 0.65 μg/mg respectively which were up to 2 and 14 times lower than the highest beta-carotene production under the slow-release salt stress method.