| abstract |
It is intended to provide a method of separating and purifying PHA whereby cell constituents other than PHA particles can be efficiently removed from PHA-containing microbial cells and thus highly pure PHA can be obtained at a high yield without causing any serious decrease in molecular weight, and a method of obtaining PHA grain aggregates. Namely, a method of collecting PHA which comprises subjecting an aqueous suspension of PHA-containing microbial cells to a mechanical disruption treatment at a low temperature and adding an alkali to thereby efficiently disrupt the microbial cells and, after collecting PHA, treating with an enzyme and/or a surfactant. Moreover, the PHA particle size can be enlarged by suspending the PHA in a hydrophilic solvent and/or water and stirring the suspension at a temperature lower than its boiling point to thereby induce aggregation. |