Improving PHA production by mixed microbial culture through the integration of a selective VFA extraction step

The study presents the results of a study focusing on a multi-stage process for efficient polyhydroxyalkanoates (PHA) production from nutrient-rich sheep cheese whey. The key innovation was the addition of a volatile fatty acid (VFA) extraction stage using a non-porous silicone membrane. This resulted in the generation of a retentate and permeate stream with optimal carbon-to-nitrogen ratio for the selection and PHA accumulation stages, respectively. Furthermore, no nutrient addition was required in the selection step. This approach resulted in significantly higher improvements in terms of PHA yield, showcasing its potential for sustainable efficient biopolymer production from nutrient-rich substrates.