Biosynthesis and characterization of polyhydroxyalkanoates in the polysaccharide-degrading marine bacterium Saccharophagus degradans ATCC 43961.

The marine bacterium Saccharophagus degradans was investigated for the synthesis of polyhydroxyalkanoates (PHAs), using glucose as the sole source of carbon in a two-step batch culture. In the first step the microorganism grew under nutrient balanced conditions; in the second step the cells were cultivated under limitation of nitrogen source. The biopolymer accumulated in S. degradans cells was detected by Nile red staining and FT-IR analysis. From GC–MS analysis, it was found that this strain produced a homopolymer of 3-hydroxybutyric acid. The cellular polymer concentration, its molecular mass, glass transition temperature, melting point and heat of fusion were 17.2 ± 2.7% of dry cell weight, 54.2 ± 0.6 kDa, 37.4 ± 6.0 °C, 165.6 ± 5.5 °C and 59.6 ± 2.2 J g−1, respectively. This work is the first report determining the capacity of S. degradans to synthesize PHAs. [ABSTRACT FROM AUTHOR]