Autor(es): Didion, Yannick Patrice ; Tjalsma, Tjalling ; Malankowska, Magdalena ; Su, Ziran ; Matos, Mariana ; Pinelo, Manuel ; Crespo, Joao ; Brazinha, Carla
Data: 2025
Identificador Persistente: http://hdl.handle.net/10362/185417
Origem: Repositório Institucional da UNL
Assunto(s): Chemistry(all); Environmental Chemistry; Chemical Engineering(all); Industrial and Manufacturing Engineering; SDG 7 - Affordable and Clean Energy; SDG 12 - Responsible Consumption and Production
Funding Information: This work was funded by the Novo Nordisk Foundation within the framework of the Fermentation-based Biomanufacturing Initiative (FBM), grant number: NNF17SA0031362. Furthermore, the authors gratefully acknowledge the PhD students Jorge Viana, Suchintan Mondal and technician Nuno Costa (Universidade NOVA de Lisboa, Faculdade de Ciências e Tecnologia (FCT)), for their help in sample preparation, handling of equipment and data analysis. Publisher Copyright: © 2025 The Author(s)
The use of conventional plastics in our modern society presents many environmental problems, both due to the accumulation of waste in ecosystems and CO2 emissions. Polyhydroxyalkanoates (PHAs), such as the co-polymer polyhydroxy(butyrate-co-valerate) (PHBV), could serve as an alternative due to their biodegradability, biocompatibility and production from renewable raw materials. However, the downstream processing of PHBV often relies on organic solvents and harsh process conditions. This study presents a novel optimized downstream process for the extraction and purification of PHBV from mixed microbial cell (MMC) biomass, as well as recycling of the solvents used in the process. For this purpose, hydrophobic natural deep eutectic solvents (NADESs) based on the terpenes thymol and menthol were prepared, and their Hansen solubility parameters (HSPs) as well as physicochemical characteristics such as viscosity and relative polarity were analyzed, before optimization of the process was carried out. Using NADESs has several advantages over traditional solvents and extraction methods due to their low toxicity, biodegradability and tunability for different applications. After screening, the most effective NADES proved to be thymol and decanoic acid in a 1:1 M ratio, while methanol was used as an anti-solvent in a 1:3 volumetric ratio. The use of these solvents for the extraction of PHBV was then optimized and a final PHBV yield of ≈ 85 wt% and purity of ≈ 92 wt% was achieved. Furthermore, both the NADES and the methanol were recycled, closing the process loop. These results were promising, as yields were comparable to those of organic solvents. Moreover, analysis of HSPs and physicochemical characteristics could help to streamline the identification process of worthwhile NADESs solvents for use in extraction.
