title: OPTIMIZATION OF SALT CONCENTRATIONS FOR A HIGHER CAROTENOID PRODUCTION IN DUNALIELLA SALINA (CHLOROPHYCEAE)(1).
abstract: Dunaliella salina (Dunal) Teodor, when treated over 25 d with a wide range of NaCl salinities (0.6-4.5 M), showed its maximal growth potentialities at 1.5-3.0 M NaCl and was able to survive even at 4.5 M NaCl. Sodium concentrations increased significantly at the supraoptimal salinities, reaching up to 5 mmol · g(-1) dry weight (dwt) at 4.5 M NaCl. Interestingly, ability of D. salina to take up essential mineral nutrients was not impaired by increased salinity. As for growth, chl concentrations were maximal in the 1.5-3.0 M NaCl range. Interestingly, carotenoid concentrations increased with the increasing salinity. The highest values of total antioxidant activity (5.2-6.9 mg gallic acid equivalents [GAE] · g(-1) dwt), antiradical activity, and reducing power were measured at 1.5-3.0 M NaCl. As a whole, these results showed that at 1.5-3.0 M NaCl, D. salina produce appreciable antioxidant level. But, once it reaches its growth maximum, a salt addition up to 4.5 M could enhance its carotenoid yield.
authors.affiliation: Laboratory of Extremophile Plants (LPE), Biotechnology Center of Borj-Cedria, P.O. Box 901, Hammam-Lif 2050, Tunisia.
authors.forename: Nèjia
authors.initials: N
authors.lastname: Farhat
authors.affiliation: Laboratory of Extremophile Plants (LPE), Biotechnology Center of Borj-Cedria, P.O. Box 901, Hammam-Lif 2050, Tunisia.
authors.forename: Mokded
authors.initials: M
authors.lastname: Rabhi
authors.affiliation: Laboratory of Extremophile Plants (LPE), Biotechnology Center of Borj-Cedria, P.O. Box 901, Hammam-Lif 2050, Tunisia.
authors.forename: Hanen
authors.initials: H
authors.lastname: Falleh
authors.affiliation: Laboratory of Extremophile Plants (LPE), Biotechnology Center of Borj-Cedria, P.O. Box 901, Hammam-Lif 2050, Tunisia.
authors.forename: Jihène
authors.initials: J
authors.lastname: Jouini
authors.affiliation: Laboratory of Extremophile Plants (LPE), Biotechnology Center of Borj-Cedria, P.O. Box 901, Hammam-Lif 2050, Tunisia.
authors.forename: Chedly
authors.initials: C
authors.lastname: Abdelly
authors.affiliation: Laboratory of Extremophile Plants (LPE), Biotechnology Center of Borj-Cedria, P.O. Box 901, Hammam-Lif 2050, Tunisia.
authors.forename: Abderrazak
authors.initials: A
authors.lastname: Smaoui
keywords: antioxidant activities; growth; nutritional behavior; photosynthetic pigments; unicellular alga