The present invention has an object to provide a method for separating and
purifying a PHA without causing a serious decrease of the molecular
weight to obtain a highly pure PHA in a high yield, which comprises
efficiently removing cell components other than PHA particles from a
cultured PHA-containing microbial cell. Another object of the present
invention is to provide a method for obtaining an agglomerate of PHA
particles.The method for recovering a PHA according to the present
invention is a method which comprises efficiently disrupting a cell to
recover the PHA by carrying out a physical disruption treatment and an
alkali addition at low temperature for an aqueous suspension of the
PHA-containing microbial cell, and then treating the PHA with an enzyme
and/or a surfactant. Moreover, the particle diameter of the PHA may be
enlarged by suspending the PHA in a hydrophilic solvent and/or water, and
stirring at a temperature equal to or below the boiling point of said
suspension, to agglomerate said PHA.