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Dunaliella salina cells in different culture conditions. (A) Green cell from a non-stressed culture. (B) Stressed cell turning orange. (C)

Dunaliella salina cells in different culture conditions. (A) Green cell from a non-stressed culture. (B) Stressed cell turning orange. (C)

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The physiology of the unicellular green alga Dunaliella salina in response to abiotic stress has been studied for sev-eral decades. Early D. salina research focused on its remarkable salinity tolerance and ability, upon exposure to vari-ous abiotic stresses, to accumulate high concentrations of β-carotene and other carotenoid pigments valued highly...

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... eukaryotic microalgae, the relatively unique ability to accumulate glycerol and β-carotene in response to osmotic stress has made the halotolerant, unicellular, green alga Dunaliella salina ( Fig. 1) an ideal model or- ganism for dissecting the molecular mechanism(s) of os- motic stress responses ( Cowan et al. 1992, Pick 1998. In contrast to the intensively studied chlorophyte Chlam- ydomonas reinhardtii (Lefebvre and Silflow 1999, Harris 2001, Hema et al. 2007, León et al. 2007, Merchant et al. 2007), relatively few studies have ...
Context 2
... plastids, after the formation of IPP by the MEP path- way as described above, three consecutive condensation reactions, which are catalyzed by prenyltransferases (Fig. 1998). In this investigation, carotenoid biosynthetic en- zymes, including PSY or PDS, were not enhanced at the transcriptional and translational levels under β-carotene overproducing conditions, whereas the activity of a key lipid biosynthesis regulatory enzyme, acetyl-CoA car- boxylase, increased dramatically. Additionally glycerol- ...

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... Similar stoichiometry was reported for psbS in HL stressed C. reinhardtii 38 . CBR was previously shown to bind the carotenoids lutein and zeaxanthin alongside chlorophyll a [39][40][41][42][43] . CBR may bind some of the accumulated xanthophylls and chlorophylls of the degraded LHCII, dissipating energy from excited chlorophylls to carotenoids before ROS are formed, thereby protecting against PI (Figs 4 and S5-S7). ...
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... As mentioned above, a protective effect against environmental stressors exerted on Dunaliella spp. is the overaccumulation of organic compounds (as a result of early rapid and long-term responses) such as carotenoids (e.g., α-carotene, β-carotene, lutein, and zeaxanthin), glycerol, fatty acids [e.g., α-linolenic (18:3), oleic (18:1), and palmitic (16:0) acids], and many others (Fig. 2) [18,[71][72][73][74]. These robust defense strategies have ultimately been exploited for commercial purposes. ...
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Preprint
After a 1.5 year screening survey in the lagoons of Western Greece in order to isolate and culture sturdy species of microalgae for aquaculture or other value added uses, as dictated primarily by a satisfactory potential for their mass-culture, five species emerged and their growth was monitored in laboratory conditions. Amphidinium carterae, Nephroselmis sp., Tetraselmis sp. (var. red pappas), Asteromonas gracilis and Dunaliella sp. were batch cultured using low (20 ppt), sea (40 ppt) and high salinity (50 or 60 or 100 ppt) and in combination with a low (2000 lux) and high (8000 lux) intensity of illumination. The results exhibited that all these species can be grown adequately in all salinities and with best growth in terms of maximum cell density, specific growth rate (SGR) and biomass yield (g dry weight/L) at high illumination (8000 lux). The five species examined exhibited different responses in the salinities used, Amphidinium clearly does best in 20 ppt far better than 40 ppt and even more than 50 ppt. Nephroselmis and Tetraselmis grow almost the same in 20 and 40 ppt and less well in 60 ppt. Asteromonas does best in 100 ppt although it can grow quite well in both 40 and 60 ppt. Dunaliella grows equally well in all salinities (20-40-60 ppt). Concerning productivity as maximum biomass yield at the end of the culture period, first rank is occupied by Nephroselmis with ~3.0 g d.w./L, followed by Tetraselmis (2.0 g/L), Dunaliella (1.58 g/L), Amphidinium (1.19 g/L) and Asteromonas (0.7 g/L) with all values recorded at high light (8000 lux).
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... One of the well-known varieties of green microalga that is economically attractive because of its source of useful materials such as carotene and glycerol is Dunaliella salina (Hosseini Tafreshi and Shariati 2009;Thiagarajan et al. 2019). Given that this microalga has some unique characteristics, it can be a beneficial specimen to investigate the pathway of algae reaction to different condition changes (Ramos et al. 2011). One of the aquatic species present in the first categories of the food chain is microalgae, and also, the microalgae have a prominent role in cleaning up their living environment. ...
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