Integrated biorefinery from Arthrospira platensis biomass as feedstock for bioethanol and lactic acid production

Abstract

An integrated biorefinery for ethanol and lactic acid production from the biomass of cyanobacterium Arthrospira platensis was investigated. Different pretreatments consisting of supercritical fluid extraction (SFE) and microwave assisted extraction (MAE) with non-polar (MAE-NPS) and polar solvents (MAE-PS) were tested on cyanobacterial biomass to obtain bioactive metabolites and the resulting residual biomass was used as a substrate for fermentation with Saccharomyces cerevisiae LPB-287 and Lactobacillus acidophilus ATCC 43121 to produce ethanol and lactic acid, respectively. The maximum concentrations achieved in our processes were 3.02±0.07 g/L of ethanol by the MAE-NPS process at 120 rpm 30 ºC, and 9.67±0.05 g/L of lactic acid by the SFE process at 120 rpm 37 ºC. Our results suggest that the proposed approach can be successfully applied in bioactive metabolites extraction and subsequently in the production of Ethanol and Lactic acid from A. platensis depleted biomass.