Environmentally friendly method for poly(3-hydroxybutyrate) recovery based on physical adsorption on a solid inorganic inert adsorbent

Abstract The extraction of intracellular polyhydroxyalkanoates involves different operations to ensure proper removal. In this process, the main aspects to be considered are: costs, recovery efficiency, product properties preservation and use of a low-toxicity solvent. Thus, a method for recovery of poly(3-hydroxybutyrate) [P(3HB)] by physical extraction with solid phase adsorption using a solid inorganic inert adsorbent (SIIA) and subsequent recovery with an alternative solvent was developed. Cells of Ralstonia solanacearum rich in P(3HB) were produced by bioprocessing in a shaker. The SIIA used was talc and, among the tested solvents, dichloromethane, a solvent of lower toxicity than chloroform, but equivalent in efficiency, was selected. The method made it possible to extract 65% of P(3HB), a 88.75% reduction in hydrophobic solvent, unlimited reuse of the SIIA and prevention of polymer fragmentation, resulting in a practical and cheaper process.