Techno-economic analysis as a valuable tool for the selection of high-potential extractive fermentation approaches for large-scale prodigiosin production

Abstract

Prodigiosin is a promising microbial red pigment with several therapeutic properties. Unfortunately, production through fermentation is hampered by product inhibition, resulting in low titers, high production costs, and an elevated price of the final product. It is of the upmost importance to develop cost-effective strategies for the intensification of this metabolite. Previously, we developed a strategy for prodigiosin production using a low-cost medium successfully coupled to a mineral oil extractive phase. In the present work, we analyze through economical modelling the developed strategies, while considering the upstream and downstream processing, aiming to evaluate the economic feasibility of each and determine the best approach for large scale production. As a production benchmark, a reported method for prodigiosin extractive fermentation using micellar ATPS (81 % recovery) was included. From an economic perspective, the best approach resulted in processing only the mineral oil fraction at continuous operation, obtaining a 4.73-fold and 16.77-fold cost per mg decrease when compared to batch and the micellar approach, respectively. The optimum operational parameters to generate 1 kg of prodigiosin at continuous scale were 2,431 L reactor volume with a 91.02 L/h flow. Based on the obtained results, it is possible to propose the mineral oil approach as a cost-effective strategy for simultaneous prodigiosin production and direct extraction. This approach yields higher upstream yields, a relatively high product purity level (∼90 %), and results in a competitive production cost of USD $25 x 10-4 per mg.