High yield production of polyhydroxyalkanoates from soybean oil by Ralstonia eutropha and its recombinant strain

High yield production of polyhydroxyalkanoates (PHAs) by Ralstonia eutropha H16 and its recombinant strain PHB(-)4/pJRDEE32d13 (a PHA-negative mutant harboring Aeromonas caviae PHA synthase gene, phaC(Ac)) from renewable inexpensive soybean oil was investigated. The PHA production by the wild-type strain H16 was achieved with a high dry cells weight (118-126 g/l) and a high poly[(R)-3-hydroxybutyrate] [P(3HB)] content per dry cells of 72-76% (w/w). A copolymer of 3HB with 5 mol% (R)-3-hydroxyhexanoate, P(3HB-co-5 mol% 3HHx), could be produced from soybean oil as a sole carbon source by the recombinant strain PHB(-)4/pJRDEE32d13 with a high dry cells weight (128-138 g/l) and a high PHA content of 71-74% (w/w). The reproducible results of PHA production in the presence of soybean oil as a sole carbon source was obtained with a high yield at a range of 0.72 to 0.76 g-PHA per g-soybean oil used. (C) 2003 Elsevier Ltd. All rights reserved.