Open AccessMole Fraction Control of Poly([R]‐3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHB/HV) Synthesized by Paracoccus denitrificans
Author(s) -
Mothes G.,
Ackermann J.U.,
Babel W.
Publication year - 2004
Publication title -
engineering in life sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.547
H-Index - 57
eISSN - 1618-2863
pISSN - 1618-0240
DOI - 10.1002/elsc.200320029
Subject(s) - valeric acid , acetic acid , paracoccus denitrificans , substrate (aquarium) , copolymer , mole fraction , fermentation , polyhydroxyalkanoates , polymer , materials science , nuclear chemistry , chemistry , polymer chemistry , organic chemistry , bacteria , biology , enzyme , ecology , genetics
Different substrate mixtures of acetic acid and valeric acid were used to synthesize copolymers of poly([R]‐3‐hydroxybutyrate‐ co ‐3‐hydroxyvalerate) (PHB/HV) with Paracoccus denitrificans under N‐limited conditions. A correlation between the substrate ratio and HV content was found in batch experiments, which seemed to be suitable to produce a number of defined copolymers. In fed‐batch fermentation, such correlation could only be found with carbon substrate mixtures of very restricted composition. Due to the individual substrate consumption rates with this technique, a polymer with 16.5 mol.‐% HV content [w/w] could be reproducibly synthesized. However, under N‐limited chemostatic cultivation conditions it was possible to produce a spectrum of definitely composed copolymers (3.0 %–46.3 mol.‐% HV) from different mixtures of acetic acid and valeric acid.