Polyhydroxyalkanoates (PHA) | Physiology of PHA metabolism | Producers of PHA | Carbon sources for the production of PHAs |

Properties of PHA | Functions of PHA | Biochemical in the metabolism of PHA | Biodegradability Of PHA | Applications of PHAs

PHA Info

Physiology of PHA Metabolism

Bacteria synthesis and store PHAs when they lack the complete range of nutrients required for cell division but have generous supply of carbon. Quantity of PHA accumulated increased as the carbon to nitrogen ratio increased [3]. The biosynthesis of PHA was shown to be initiated by magnesium or sulphate deficiency, as well as a nitrogen, phosphate [4, 5] and/or oxygen limitation [6].

Cell divisions of Cupriavidus necator H16 during active growth phase


Formation of small P(3HB) granule near the nucleoid region in C. necator H16 grown on palm kernel acid oil (PKAO) with the supplementation of high nitrogen concentration (low C/N ratio)



C. necator H16 grown in minimal medium (MM) supplemented with 50 mM urea as the nitrogen source (low C/N ratio)


C. necator H16 with approximately 60 wt% of P(3HB) after cultivation for 72 h in MM with 5 g/L PKAO and 5 mM of urea (high C/N ratio)

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