Biosynthesis and characterization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymers using jatropha oil as the main carbon source

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] copolymers were produced using jatropha oil as the carbon source. P(3HB-co-3HV) with a 3HV monomer as high as 42 mol% was produced by wild-type Cupriavidus necator H16 from a mixture of jatropha oil and sodium valerate, and P(3HB-co-3HHx) with a 3HHx monomer of 3 mol% was produced by transformant C. necator PHB−4/pBBREE32d13 harboring Aeromonas caviae PHA synthase, using jatropha oil as the sole carbon source. The results of differential scanning calorimetry, thermogravimetric analysis and gel permeation chromatography revealed that the copolymers produced from jatropha oil were essentially the same as those produced from other, more established carbon sources, such as sugars and other plant oils. This study demonstrates that jatropha oil is a potential renewable carbon source for the large-scale production of copolymers by C. necator and its transformant.