Production of exopolysaccharide by Botryococcus braunii CCALA 778 under laboratory simulated Mediterranean climate conditions

This work aims at optimizing biomass and exopolysaccharide productivities of Botryococcus braunii CCALA 778 grown under simulated Mediterranean climate conditions. The effect of temperature and light irradiance on biomass and exopolysaccharide productivity were studied. Our results show that light:dark cycles lead to higher biomass and sugar productivities in comparison to continuous illumination. The optimal temperature of Botryococcus braunii CCALA 778 ranges from 23 to 26°C, although it is tolerant to low temperatures (4°C). The highest exopolysaccharide productivity (0.29±0.05g exopolysaccharide L−1day−1) was obtained during high light irradiance (simulating a summer day) and temperature controlled at 26°C. •Optimizing biomass and exopolysaccharide productivity of continuous cultures under simulated Mediterranean climate•Study of the combined effects of light and temperature conditions on biomass and exopolysaccharide productivity•Maximum exopolysaccharide productivity under light:dark cycles with high light intensity and temperature controlled