Synergistic effect of UV radiation and nutrient limitation on Chlorella fusca (Chlorophyta) cultures grown in outdoor cylindrical photobioreactors

0440825 - MBÚ 2015 RIV DE eng J - Journal Article
Malpartida, I. - Jerez, C.G. - Morales, M.M. - Nascimento, E. - Freire, I. - Ezequiel, J. - Rico, R.M. - Peralta, E. - Malapascua, J.R. - Florez, Y. - Masojídek, Jiří - Abdala, R. - Figueroa, F.L. - Navarro, E.
Synergistic effect of UV radiation and nutrient limitation on Chlorella fusca (Chlorophyta) cultures grown in outdoor cylindrical photobioreactors.
Aquatic Biology. Roč. 22, č. 2 (2014), s. 141-158. ISSN 1864-7790. E-ISSN 1864-7782
Grant - others:Univ. Málaga, Ministry of Economy and Competitiveness of Spanish Government(ES) Acción Complementaria CTM2011-15659-E; Spanish Ministry of Economy and Competitiveness of Spanish Government(ES) BFU2010-22053
Institutional support: RVO:61388971
Keywords : bio-optics * radiation * Chlorella * chlorophyll
Subject RIV: EE - Microbiology, Virology
Impact factor: 1.258, year: 2014

This study assessed the interactive effects of UVR and nutrient depletion on Chlorella fusca cultures on the production and accumulation of particular biomolecules. To accomplish this, algae were grown for 5 d in outdoor thin-layer cascade cultivators under 3 nutrient treatments (full nutrients, -N and -S) and then transferred to outdoor cylindrical photobiore-actors for another 5 d. Cultures were then exposed to full solar radiation (PAB) and decreased UVR. During the last 5 d, bio-optical properties, photosynthetic activity, pigments, biochemical composition and oxidative stress were assessed. Initially, nutrient depletion caused changes in productivity and cell number in a manner that affected biochemical composition. After 3 d, the percentage of lipids in the cultures under N deprivation reached values appropriate for being used as feed or food additives or for energy applications (35% of lipid content), regardless of the light conditions. A longer exposure (5 d) resulted in interactive effects of light and nutrient conditions. Specifically, PAB increased lipid content in all cases (1.3- to 2.3-fold), but particularly under S deprivation. Longer exposure to PAB also increased oxidative stress in UVR and nutrient-limited treatments (-N and -S). These results showed that the benefits expected from nutrient depletion (increase in biomolecule content e.g. lipids, carbohydrates and pigments) were modulated by the negative effects of algal UVR acclimation costs.
Permanent Link: http://hdl.handle.net/11104/0243930