Polyhydroxyalkanoates continuous process

Fig. 1 Electron-microscopic pictures of polyhydroxyalkanoate (PHA)-rich Cupriavidus necator DSM 545 cells cultivated in a continuous fermentation process on glucose. Magnification x20,000...

Polyhydroxyalkanoates (PHAs) are homo- or heteropolyesters synthesized and intracellularly stored by numerous prokaryotes. They can be produced in large quantities from renewable resources by means of well known fermentation processes and the imposition of particular culture conditions, and a number of physical or chemical methods are known to extract them from the producing biomass. Production processes such as batch, semi-batch and continuous fermentation are all known to work. PHAs have properties similar to those of some polyolefins. This, combined with the fact that they are fully and rapidly biodegraded under the appropriate conditions, has generated a high interest in them as substitutes to petroleum-based polymers in many applications [1]. 

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