Holistic evaluation of PHA extraction methods: insights from LCA, eLCC, and physico-chemical characterization

This study evaluates various extraction methods of polyhydroxyalkanoates (PHAs) from bacterial biomass, specifically chemical digestion and solvent extraction. Life cycle assessment (LCA) and environmental life cycle cost (eLCC) methodologies were used to select those with the best environmental and economic performance resulting in those based in chemical digestion using NaOH and H2O2. Additionally, the characteristics of PHA extracted with both methods were also evaluated in PHA-rich biomass, obtained from a process with a mixed culture and with used cooking oil (UCO) as substrate. The results of the physicochemical characterization of the extracted PHA show that NaOH stands out for its ability to denature proteins (breaking the biomass to facilitate PHA extraction) and to remove triacylglycerides (TAGs) by saponification.