IMPROVEMENT OF LIPID PRODUCTIVITY ON Chlorella vulgaris USING WASTE GLYCEROL AND SODIUM ACETATE

Abstract

Although microalgae have potential as a raw material for biodiesel production it is necessary to increase biomass and lipids productivity. One way to achieve this goal is the implementation of mixotrophic cultures and the regulation of carbon/nitrogen ratio. The present work aims to improve the productivity of biomass and lipids in Chlorella vulgaris UTEX 1803 using waste glycerol from biodiesel production (1, 5 and 10% v/v) and sodium acetate (5, 10 and 20 mM) as carbon sources, with modification of the initial concentration of nitrogen (1.02, 1.47 and 2.94 mM de NaNO3). All experiments were performed at 23±1ºC, with light-dark cycles of 12:12h during five days. In biomass production, a significant increase was achieved (80% higher that cultures without modification). Lipid productivities were also found 2.83 and 3.5 times greater than control. Results show the possibility of increasing the production of biomass and lipids by applying the carbon/nitrogen ratio, using waste glycerol. This opens up great possibilities for the re-use of this residue, thus increasing the sustainability of the process in general. Also, it has been proved that -due to its low cost- carbon/nitrogen ratio using sodium acetate is an interesting alternative.

Keywords

• Cultivo Mixotrófico
• Microalgas
• Biomasa
• Lipidos
• Biodiesel