Abstract

Algae and microalgae are used as a source of different biomolecules, such as lipids and carbohydrates. Among carbohydrates, polysaccharides, such as beta-glucans, are important for their application as antioxidants, antisepsis, and immunomodulators. In the present work, the beta-glucans production potential of Microchloropsis salina was assessed using two different culture conditions: a high-density batch and a modeled high-density fed-batch. From the biochemical parameters determined from these two cultures conditions, it was possible to establish that the modeled high-density fed-batch culture improves the biomass growth. It was possible to obtain a biomass productivity equal to 8.00 x 10(-2) +/- 2.00 x 10(-3) g/(L x day), while the batch condition reached 5.13 x 10(-2) +/- 4.00 x 10(-4) g/(L x day). The same phenomenon was observed when analyzing the beta-glucans accumulation, reaching volumetric productivity equal to 5.96 x 10(-3) +/- 2.00 x 10(-4) g of product/(L x day) against the 4.10 x 10(-3) +/- 2.00 x 10(-4) g of product/(L x day) obtained in batch conditions. These data establish a baseline condition to optimize and significantly increase beta-glucan productivity, as well as biomass, adding a new and productive source of this polymer, and integrating its use in potential applications in the human and animal nutraceutical industry.