title: Selective recovery of polyhydroxyalkanoate inclusion bodies from fermentation broth by dissolved-air flotation.
abstract: Selective dissolved-air flotation for the separation of medium-chain-length polyhydroxyalkanoate (PHA) inclusion bodies (IBs) from Pseudomonas putida cell debris is investigated. Measurements show that both P. putida cell debris and PHA IBs have an iso-electric point of approximately pH 3.5. Selective aggregation and as a result selective flotation of PHA IBs was observed near this pH. Qualitative prediction of the aggregation behaviour was possible on the basis of the Van der Waals, hydrophobic and electrostatic interactions. In some cases however, the stability of the suspension could not be explained with these forces alone. It was therefore suggested that additional interactions, such as steric/brush effects, play an important role in the aggregation process.
authors.affiliation: Department of Biotechnology, Delft University of Technology Julianalaan 67, 2628 BC Delft, The Netherlands.
authors.forename: Pim
authors.initials: P
authors.lastname: van Hee
authors.forename: Andrea C M R
authors.initials: AC
authors.lastname: Elumbaring
authors.forename: Rob G J M
authors.initials: RG
authors.lastname: van der Lans
authors.forename: Luuk A M
authors.initials: LA
authors.lastname: Van der Wielen
mesh_terms: D000388:Air; D005285:Fermentation; D057927:Hydrophobic and Hydrophilic Interactions; D002479:Inclusion Bodies; D011091:Polyesters; D016958:Pseudomonas putida; D055672:Static Electricity
chemical_list: D011091:Polyesters