Polyhydroxybutyrate production by Saccharophagus degradansusing raw starch as carbon source

Biosynthesis of poly(3‐hydroxybutyrate) (PHB) from raw starch as the carbon source by the polysaccharide‐digesting bacteria Saccharophagus degradanswas investigated in a fed‐batch culture. The production and properties of the PHB synthesized from starch were compared to those obtained using glucose as carbon source. In fed‐batch cultures, S. degradansaccumulated 21.35 and 17.46% of PHB, using glucose or starch as carbon source, respectively. The physical properties of the biopolymer produced from each carbon source were similar between them. Molecular mass, melting temperature and heat of fusion were 54.23 kDa, 165.61°C and 59.59 J/g, respectively, using glucose; and 57.07 kDa, 174.31°C and 67.66 J/g, respectively, using starch. This is the first work describing the capability of S. degradansto utilize raw starch as the sole carbon source for the production of PHB.