Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9604504 | Journal of Biotechnology | 2005 | 10 Pages |
Abstract
Performance of Dunaliella salina cultures outdoors in a closed tubular photobioreactor has been assessed. Optimization of conditions involved verification of the effect of several determining factors on the yield of both biomass and carotenoids. Maximal biomass productivity (over 2 g (dry weight) mâ2 dâ1 or 80 g mâ3 dâ1) was achieved at 38 cm sâ1, flow rate; 2 à 109 cells lâ1, initial population density; 25 °C, temperature; semi-continuous regime, keeping a cell density interval between 2 à 109 and over 4 à 109 cells lâ1. Coverage of the tubular loop with a sunshade screen to avoid light-induced damage of cells was essential to maintain growth performance. The cellular β-carotene level increased significantly during the light period, as also did that of lutein. The rise in the β-carotene level could be accounted by the 9-cis-isomer, with all-trans-β-carotene remaining steady during the light period. By sunset, the ratio between 9-cis- and all-trans-isomers of β-carotene amounted to 1.5, with over 60% of total β-carotene corresponding to the 9-cis-isomer. Removal of sunshade enhanced carotenoid accumulation by cells to reach up to 10% of dry biomass. Cultivation of Dunaliella in closed tubular photobioreactor, thus represents a suitable approach for the production of a high-quality microalgal biomass enriched in the valuable 9-cis-isomer of β-carotene and lutein.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Bioengineering
Authors
Mercedes GarcÃa-González, José Moreno, J. Carlos Manzano, F. Javier Florencio, Miguel G. Guerrero,