Effects of cultivation conditions on Chlorella vulgaris and Desmodesmus sp. grown in sugarcane agro-industry residues

• DOI: 10.1016/j.biortech.2021.125949
• Publication Date: 2021-09-17T15:28:17Z
• Authors: Gabriela F. Ferreira; Luisa F. Ríos Pinto; Rubens Maciel Filho; Leonardo V. Frego...
• Keywords: Vinasse; Biofertilizer; Bagasse; Chlorella vulgaris

Large-scale microalgae cultivation is often associated with high costs, and nutrients account for a significant part. However, the use of cheaper nutrients, carbon, and water sources could reduce expenses. This study aims to produce Chlorella vulgaris and Desmodesmus sp. cultivated in sugarcane biorefinery residues bagasse and vinasse. A biofertilizer from bagasse biochar was produced and characterized, and a pre-treatment by filtration was performed on vinasse. The effects of varying growth conditions (antibiotic, vinasse, and biofertilizer concentrations; air flowrate; pH; light intensity; and photoperiod) were discussed based on the results of a Plackett-Burman design. The highest cell density was achieved by Desmodesmus sp. (46·106 cells mL-1 from an initial 6.5·106 cells mL-1) using vinasse (20%) and biofertilizer (1 g L-1). Specific metabolite accumulation was also observed. Under stress conditions, 21.3% lipids and 51.0% carbohydrates were obtained for two different cultivations. Using 1 g L-1 of biofertilizer, biomass composition had 74.8% proteins.