PHA/PHB

Polyhydroxyalkanoates (PHAs) are a family of bacterially synthesized biopolyesters with biodegradability, biocompatibility, thermoprocessibilty, and flexible strengths. Poly-(R)-3-hydroxybutyrate (PHB) was the first PHA discovered and has been the best-studied PHA member. PHAs have found applications in the form of packaging materials including films, boxes, coating, fibers and foam materials, biofuels, medical implants, and drug delivery carriers. For large-scale applications such as biodegradable packaging materials, the cost and properties of PHAs are very important. Over the past years, process development and metabolic engineering approaches have been adopted to develop recombinant PHA production strains for improving the strains’ ability to produce PHA, and for changing the PHA structures to obtain better thermal and mechanical properties. This article will describe major past and recent achievements in PHA/PHB.