Strategies of poly(3-hydroxybutyrate) synthesis by Haloarcula sp. IRU1 utilizing glucose as carbon source: Optimization of culture conditions by Taguchi methodology.

We investigated optimization of poly(3-hydroxybutyrate) (PHB) production by Haloarcula sp. IRU1 in a batch culture system. Various batch experiments were carried out at different carbon source concentrations [glucose, at 1-8% (w/v)], phosphorus source concentrations [K(2)HPO(4), KH(2)PO(4), Na(3)PO(4) and Na(2)HPO(4) at 0.001-0.016% (w/v)], nitrogen source concentrations [NH(4)Cl, yeast extract, peptone and tryptone at 0.1-0.8% (w/v)] and temperatures [37-55°C]. By these experiments, optimum production conditions were determined using the Taguchi method. The results showed the highest PHB production by Haloarcula sp. IRU1 (63.0% of cell dry weight) in the presence of 2g/l glucose, 0.2g/l NH(4)Cl, 0.004 g/l KH(2)PO(4) and temperature (42°C). In overall, the results of this study showed that Haloarcula sp. IRU1 has a high potential for synthesis of PHB from glucose.