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

Aquatic Biology

C. G. Jerez¹  P. Nascimento¹  E. Peralta¹  J. R. Malapascua¹  Y. Florez¹  I. Malpartida¹  E. Navarro¹  R. Abdala¹  I. Freire¹  J. Ezequiel¹  F. L. Figueroa¹  M. M. Morales¹  J. Masojidek¹  R. M. Rico¹ 

关键词: Bio-optic;    Chlorella fusca;    In vivo chlorophyll fluorescence;    Photosynthetic pigments;    UV radiation;    Lipids;    Lipid peroxidation;    Proteins;    Biochemical composition;   

DOI  :  10.3354/ab00595

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: 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 photobioreactors 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.

【 授权许可】

Unknown