Microalgal biotechnology: Carotenoid and glycerol production by the green algae Dunaliella isolated from the Gave-Khooni salt marsh, Iran

Abstract

In this study, carotenoid and glycerol production in two unicellular green algae (aìå~äáÉää~=ë~äáå~ and aK=îáêáÇáë) isolated from the Gave-Khooni salt marsh grown in media containing five different salt concentrations (0.17, 1, 2, 3, and 4 M NaCl) were evaluated under sterile conditions. Algae growth decreased as the medium salinity increased. Optimum growth of aK=ë~äáå~ and aK=îáêáÇáë were obtained at 2 and 1 M NaCl, respectively. As salinity increased, glycerol and carotenoid production were increased in aK=ë~äáå~, whereas lower values for these products were produced in aK=îáêáÇáë under the same conditions. Furthermore, the cell color of aK=ë~äáå~ changed from green to orange-red following accumulation of carotenoid, but the color of aK=îáêáÇáë was not changed. Thereby, it seems that the Iranian aK=ë~äáå~ may be suitable for carotenoid production (betacarotene) on a large scale. In addition, since carotenoid compounds enhance the efficiency of photosynthesis and glycerol synthesis, it appears that the pathway for glycerol production and mechanisms of salt tolerance in aK=îáêáÇáë are unique from those of aK=ë~äáå~. © KSBB hÉóïçêÇëW=Dunaliella salinaI=Dunaliella viridisI=ë~äáåáíóI=Å~êçíÉåçáÇI=ÖäóÅÉêçä= = = = =

Microalgal Biotechnology and Bioenergy in Dunaliella

“…It seems that in Dunaliella, osmolyte of main for balancing the extracellular osmotic stress is glycerol, because its intracellular concentration intensively accumulates in response to any osmotic stress such as high medium salinity (Shariati, 2003;Hadi et al, 2008). Also, it shown that its intracellular concentration was linearly related to the medium osmotic pressure (Fig.…”

“…The genus Dunaliella contains several species which stand out as being the only eukaryotic and photosynthetic organisms which are able to grow in media containing an extremely wide range of salt concentrations, from 0.05 to 5.5 M NaCl (Avron & Ben-Amotz, 1992), but, optimal growth is different in various species and in order to Hadi et al, (2008) reported that optimal growth of D. salina (Iranian strain) was obtained at 2 M NaCl ( Fig. 2 and Fig.…”

“…Growth of Dunaliella salina in media containing different NaCl concentrations. The algae can grow in media containing an extremely wide range of salt concentration, from 0.17 M to 4.0 M NaCl (Hadi et al, 2008). Fig.…”

“…Intracellular glycerol content as a function of the extracellular NaCl oncentration in Dunaliella salina. Intercellular glycerol and chlorophyll content was determined in cells grown in media containing the indicated salt concentration (Hadi et al, 2008).…”

Growth and Carotenoid Production in Dunaliella spp. Isolated from Hypersaline Habitats in the Region of Essaouira (Morocco): Effect of NaNO3 Concentration

“…Dunaliella species were widely distributed in the world and live in an extremely wide range of habitats [7]. These microrganisms were cultivated in many countries to produce carotenoids [8,9], glycerol [8], proteins and vitamins [10], feeding for fish and human consumption [11,12], biofuel production [13,14] and pharmaceutical formulations [15]. Dunaliella species were also used in bioremediation for removing heavy metals and play an important role in detoxification and accumulation of heavy metals [16][17][18].…”