The halotolerant green alga Dunaliella salina (isolate SEA003) recently isolated from salt march at Zaranik nature reserve, North Sinai, (Egypt) was cultivated in the artificial seawater medium (ASW) with different salinity levels (0.5, 1, 2, 3, and 4 M), under continuous illumination of two different light intensities: 50 and 200 μmol m-²s-1, during 30 day of incubation. The maximum growth density as number of cell was recorded in media contained 2M NaCl under the high light intensity, while Chlorophyll a giving its maximum values at 1 M salinity under high light intensity. Anent values of β carotene produced by Dunaliella salina revealed that, 2 M salinity had the superiority in enhancing β carotene production during the 30 days of this study, especially under high light intensity. In contrast with β carotene productivity, Dunaliella salina gave its maximum glycerol values at the high salinity (4M). This result revealed that, the algal productivity can be controlled, as well as directed to produce a particular substance (such as carotene and glycerol) on a wide scale by controlling the growth conditions. Adjusting salinity and light intensity is likely the best strategies to achieve optimal β-carotene or glycerol production in mass cultures.
Key words: Dunaliella, ß-carotene, glycerol, salinity, light intensity
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