Waste biorefinery towards a sustainable biotechnological production of pediocin: Synergy between process simulation and environmental assessment
Ana Arias, Daniel Barreiro, Gumersindo Feijóo, Marı́a Teresa Moreira
Abstract
The development of biotechnological processes through which high added value products can be obtained, using non-valuable industrial streams, has become a primary objective in the scope of sustainability and circular economy strategies. It is in this context where this research report is framed, in which a biorefinery approach has been developed using mussel processing wastes (MPW) as a resource, thus avoiding the environmental impacts involved in their management. Through an enzymatic pre-treatment and a batch fermentation process, this waste stream is valorized, and three high added value products are obtained: pediocin, lactic acid and crude protein. To develop comparative scenarios, a detailed analysis of the environmental impacts associated with the production of pediocin at two purity levels (2.5 % and 95% w/w), using the MPW and a commercial fermentation medium (MRS) has been performed by applying the life cycle assessment (LCA) methodology. The results obtained show the great potentiality of MPW as C-source, both from an environmental, economic and technological point of view since, when compared with MRS, the carbon footprint is reduced from 24.02 to 15.87 and from 23.85 to 15.66 kg CO2 eq/kg of products for a purity of 2.5% and 95% w/w of pediocin, respectively. Besides, analogous impact reduction values are observed for the rest of the impact categories evaluated. However, certain hot spots have been identified, which future improvement studies should focus: energy and calorific requirements, mainly, as a contribution higher than 50% is observed for most of the impact categories.