Bacterial polyhydroxyalkanoate granules

K. Grage, A.C. Jahns, N. Parlane, R. Palanisamy, LA. Rasiah, J.A. Atwood, B.H. Rehm, Bacterial polyhydroxyalkanoate granules biogenesis, structure, and potential use as nano-/micro-beads in biotechnological and biomedical applications. Biomacromolecules 10 (4) (2009) 660-669. 

An additional advantage of the polyhydroxyalkanoates is that the polymers can be produced by fermentation. Certain types of bacteria produce PHAs for energy storage when they are grown in glucose solution in the absence of specific nutrients. The polymer forms as discrete granules within the bacterial cell, and it is then removed by extraction to give a white powder that can be melted and modified into a variety of different products. 

Polyhydroxyalkanoates are polyesters accumulated as energy storage materials by various bacteria in the form of intracellular granules, reaching up to 80% of bacterial biomass weight. They can be synthesized by different sources of renewable and non-renewable carbon, such as molasses (from sugar cane) and even some effluents from the food industry. Nowadays, PHAs have been obtained from bacteria and some genetically modified plants. 

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