An integrated process for the in situ recovery of prodigiosin using micellar ATPS from a culture of Serratia marcescens

BACKGROUND: In situ product recovery (ISPR), or extractive fermentation, is a strategy for the primary recovery of metabolites. A micellar aqueous two-phase system (ATPS) composed of a surfactant-rich phase was coupled to batch and continuous fermentations for the production and in situ recovery of the red alkaloid prodigiosin from Serratia marcescens. A cloud point ATPS was formed at 24 degrees C using triton X-114 and used as a production/extraction system for this metabolite, which shows therapeutic properties as antibiotic, anti-proliferative and anti-malarial activities. RESULTS: The integration of the micellar ATPS in batch fermentation resulted in the production of 342 mg prodigiosin L-1 with a recovery of 81% in the extractive phase. When a continuous fermentation was performed, based on a cloud point system, 1.2-fold prodigiosin content was obtained compared with batch mode and a recovery of 88% of the metabolite. This continuous operation resulted in 0.43 g of purified prodigiosin from a 1.5 L bioreactor with a concentration of 872 mg prodigiosin L-1 of extractive phase and a purity of 82%, demonstrating particular selectivity of the system for prodigiosin as a primary recovery method. This is the first report on the continuous production of this generally recognized secondary metabolite. CONCLUSION: The experimental approach proposed proved that an ISPR system could lead to the establishment of a more efficient process for continuous large-scale prodigiosin production. The proposal of a primary recovery strategy with only one bioprocess step enhances this metabolite production by lowering the inhibiting properties of prodigiosin for the microorganism. (C) 2016 Society of Chemical Industry