Sugarcane vinasse as feedstock for microalgae cultivation: from wastewater treatment to bioproducts generation

Vinasse is a by-product resulting from the ethanol production process. It is generated in huge volumes which are destined to fertirrigation, although has high polluting potential. Otherwise, microalgae-guided sequestration is seen as one of the more promising and sustainable solutions to mitigate CO 2 . Another advantage of microalgae production systems is their potential to utilize wastes, including sewage, leachates, and gas emissions. In this context, this research aimed to evaluate the efficiency of microalgae for vinasse preliminary treatment in terms of the remotion of nutrients (phosphorus and ammoniacal nitrogen) and organic matter. Moreover, the resultant microalgae biomass amount was characterized for bioproducts generation, such as carbohydrates, proteins, lipids content, and antioxidant, bioactive substances with high potential for both commercial and industrial use. The media cultivation supplemented with 20% or 30% of vinasse resulted in 3.16 g L −1 of biomass, 30% of carbohydrate and 20% of lipids and 3.05 g L −1 biomass, 24% of carbohydrate and 51% of lipids, respectively, in 96 h. Both treatments also resulted in a significant reduction of nutrients and chemical oxygen demand (COD). The obtained results indicate the increasing of vinasse in media cultivation can modulate the microalgae metabolism. Furthermore, is the first time that the microalgae Coelastrella sp., utilized in this work, is reported in Brazil and has its potential evaluated for the treatment of vinasse with concomitant generation of bioproducts.