Industrial scale production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)

Abstract.

Large scale production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] by Aeromonas hydrophila 4AK4 was examined in a 20,000 l fermentor. Cells were first grown using glucose as a carbon source, and polyhydroxyalkanoate (PHA) biosynthesis was triggered by the addition of lauric acid under conditions of limited nitrogen or phosphorus. When cells first grown in a medium containing 50 g glucose l^–1 were further cultivated after the addition of 50 g lauric acid l^–1 under phosphorus limitation, a final cell concentration, PHA concentration and PHA content of 50 g l^–1, 25 g l^–1, and 50 wt%, respectively, were obtained in 46 h, equivalent to PHA productivity of 0.54 g l^–1 h^–1. The copolymer produced was found to be a random copolymer, and the 3HHx fraction was 11 mol%.