A PROCESS FOR THE EXTRACTION OF POLY-3-HYDROXY-BUTYRIC ACID FROM MICROBIAL CELLS

摘要

Poly-3-hydroxybutyric acid is separated from bacterial cells by drying a finely divided stream or spray of an aqueous suspension of the cells with a gas heated to above 100 DEG C and then extracting the PHB, preferably after a lipid extraction step with a solvent such as methanol or acetone, with a PHB-solvent such as a partially halogenated hydrocarbon such as 1,2-dichloroethane, chloroform or dichloromethane. 1,2-Dichloroethane may also be used to extract PHB directly from an aqueous cell suspension without an intermediate drying step. In this case, for some bacteria, the suspension is preferably subjected to a cell disruption step, eg milling, prior to contact with the 1,2-dichloroethane.