Arthrospira platensis is a cyanobacterium that is of great biotechnological interest, particularly for the food industry, as it possesses a high content of proteins, pigments, lipids and carbohydrates. Cyanobacteria produce extracellular polymeric substances (EPS), which are co-products of secondary metabolism that present thickening or gelling properties. A 3-level factorial design was used to study the combined effect of different nitrate concentrations and photon flux density (PFD) values to evaluate the biomass and EPS production of A. platensis. The best result in terms of biomass production was obtained under condition 6 (2 g L −1 NaNO 3 and 600 μE m −2 s −1) yielding a concentration of 1.292 g L −1. However, condition 1 (0.25 g L −1 NaNO 3 and 200 μE m −2 s −1) produced the greatest EPS yield (111 mg g −1), followed by condition 9 (2 g L −1 NaNO 3 and 1000 μE m −2 s −1). FTIR analyses of EPS samples indicated the presence of carboxylate and sulfate functional groups, and rheological studies of the EPS at 5 and 10 g L −1 revealed a dilute solution behavior.

Arthrospira platensis is a cyanobacterium that exhibits a large biotechnological interest at food industry because its high protein content, pigments, lipids and carbohydrates. The extracellular polymeric substances (EPS) are co-products of secondary metabolism that present thickening or gelling property. A 3-level factorial design was used to study the combined effect of different nitrate concentrations and photon flux density (PFD) to evaluate the biomass and EPS production by Arthrospira platensis. Characterization of the EPS produced the rheological behavior were also evaluated. The best result for biomass production was obtained at condition 6 (2 g.L-1 NaNO3 and 600 µE.m-2s-1) leading a biomass concentration of 1.292 mg.L-1. Condition 1 (0.25 g.L-1NaNO3 and 200 µE.m-2s-1) produce the major EPS content (111 mg.g-1) followed by condition 9 (2 g.L-1NaNO3 and 1000 µE.m-2s-1). Rheological studies performed for the product at 5 and 10g.L-1 concentrations revealed a dilute solution behavior.

Arthrospira platensis is a cyanobacterium that exhibits a large biotechnological interest for the food industry because of its high protein content, pigments, lipids and carbohydrates. The extracellular polymeric substances (EPS) are co-products of secondary metabolism that may present thickening or gelling property. A 3-level factorial design was used to study the combined effect of different nitrate concentrations and photon flux density (PFD) to evaluate the biomass and EPS production by Arthrospira platensis. The best result for biomass production was obtained under condition 6 (2 g.L-1 NaNO3 and 600 µE.m-2s-1) leading a biomass concentration of 1.292 mg.L-1. Condition 1 (0.25 g.L-1NaNO3 and 200 µE.m-2s-1) produced the major EPS yield (111 mg.g-1) followed by condition 9 (2 g.L-1NaNO3 and 1000 µE.m-2s-1). The present of carboxylate and sulfate functional groups was identified in EPS samples. Rheological studies performed for some EPS products at 5 and 10 g.L-1 concentrations revealed a dilute solution behavior.

Arthrospira platensis is a cyanobacterium that is of great biotechnological interest, particularly for the food industry, as it possesses a high content of proteins, pigments, lipids and carbohydrates. Cyanobacteria produce extracellular polymeric substances (EPS), which are co-products of secondary metabolism that present thickening or gelling properties. A 3-level factorial design was used to study the combined effect of different nitrate concentrations and photon flux density (PFD) values to evaluate the biomass and EPS production of A. platensis. The best result in terms of biomass production was obtained under condition 6 (2 g.L-1 NaNO3 and 600 μE.m-2.s-1) yielding a concentration of 1.292 g.L-1. However, condition 1 (0.25 g.L-1 NaNO3 and 200 μE.m-2.s-1) produced the greatest EPS yield (111 mg.g-1), followed by condition 9 (2 g.L-1 NaNO3 and 1000 μE.m-2.s-1). FTIR analyses of EPS samples indicated the presence of carboxylate and sulfate functional groups, and rheological studies of the EPS at 5 and 10 g.L-1 revealed a dilute solution behavior.