Pigments in dry cells were removed by 95% (v/v) methanol for 24 h and cells were dried at 80 ºC. PHB polymer was then extracted from the samples with chloroform at 80 ºC for 1.5 h with upon shaking at 250 rpm. The chloroform extraction was preceded twice. The extracted solvent was evaporated to reduce the volume to 0.5 ml and precipitated by adding 2 ml hexane. The PHB pellet was re-dissolved and re-precipitated by 0.5 ml chloroform and 2 ml hexane