• isolation;
  • glycerine pitch;
  • P(3HB-co-4HB);
  • yellow-pigmented Cupriavidus sp



Development of bacterial strains that can utilize cheap and renewable carbon substrate will make the prices of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] competitive with synthetic plastics. Disposal of glycerine pitch, which is a scheduled waste from the oleochemicals industry, has raised awareness among communities as burning the waste literally means producing acrolein which is well known for its toxicity and adverse effects. Therefore, discovering potential application of glycerine pitch as carbon substrate is believed to overcome the waste management problem and reduce the P(3HB-co-4HB) production cost.


Cupriavidus sp. USMAHM13, a novel yellow-pigmented bacterium produced the highest 4HB composition (43 mol%) with cell dry weight and PHA content of 6.0 g L-1 and 49 wt%, respectively, through combination of glycerine pitch (5 g L-1) and 1,4-butanediol (5 g L-1) via one-stage cultivation. The yellow pigment extracts were analyzed using UV–VIS spectrophotometry and high performance liquid chromatography – mass spectrometry (HPLC-MS), which revealed that the yellow pigment might represent a new compound in the carotenoid group.


Biosynthesis of P(3HB-co-4HB) by a novel yellow-pigmented Cupriavidus sp. using glycerine pitch together with 1,4-butanediol enhanced cost efficiency and sustainability in the production of P(3HB-co-4HB).