초록
<P><B>Abstract</B></P> <P>Synthesis of polyhydroxyalkanoates (PHAs) by a new strain of <I>Cupriavidus</I> – <I>Cupriavidus eutrophus</I> B-10646 – was investigated under autotrophic growth conditions. Under chemostat, at the specific flow rate <I>D</I> =0.1h<SUP>−1</SUP>, on sole carbon substrate (CO<SUB>2</SUB>), with nitrogen, sulfur, phosphorus, potassium, and manganese used as growth limiting elements, the highest poly(3-hydroxybutyrate) [P(3HB)] yields were obtained under nitrogen deficiency. In batch autotrophic culture, in the fermenter with oxygen mass transfer coefficient 0.460h<SUP>−1</SUP>, P(3HB) yields reached 85% of dry cell weight (DCW) and DCW reached 50g/l. Concentrations of supplementary PHA precursor substrates (valerate, hexanoate, γ-butyrolactone) and culture conditions were varied to produce, for the first time under autotrophic growth conditions, PHA ter- and tetra-polymers with widely varying major fractions of 3-hydroxybutyrate, 4-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate monomer units. Investigation of the high-purity PHA specimens showed significant differences in their physicochemical and physicomechanical properties.</P> <P><B>Highlights</B></P> <P> <UL> <LI> PHA synthesis by <I>Cupriavidus eutrophus</I> В-10646 was studied in autotrophic culture. </LI> <LI> Conditions of the synthesis of PHAs with different composition have been found. </LI> <LI> Physicochemical properties of different PHA specimens have been studied. </LI> </UL> </P>