Authors
Advisor(s)
Abstract(s)
The co-culture of Cupriavidus necator DSM 428 and Pseudomonas citronellolis NRRL B-2504
was performed using apple pulp waste from the fruit processing industry as the sole carbon source to
produce poly(3-hydroxybutyrate), P(3HB) and medium-chain length PHA, mcl-PHA, respectively.
The polymers accumulated by both strains were extracted from the co-culture’s biomass, resulting in
a natural blend that was composed of around 48 wt% P(3HB) and 52 wt% mcl-PHA, with an average
molecular weight of 4.3 x 10 5 Da and a polydispersity index of 2.2. Two melting temperatures
(Tm) were observed for the blend, 52 and 174 ºC, which correspond to the Tm of the mcl-PHA and
P(3HB), respectively. P(3HB)/mcl-PHA blend films prepared by the solvent evaporation method
had permeabilities to oxygen and carbon dioxide of 2.6 and 32 Barrer, respectively. The films were
flexible and easily deformed, as demonstrated by their tensile strength at break of 1.47 +- 0.07 MPa,
with a deformation of 338 +- 19% until breaking, associated with a Young modulus of 5.42 +- 1.02 MPa.
This study demonstrates for the first time the feasibility of using the co-culture of C. necator and
P. citronellolis strains to obtain a natural blend of P(3HB)/mcl-PHA that can be processed into films
suitable for applications ranging from commodity packaging products to high-value biomaterials
Description
Keywords
apple pulp waste polyhydroxyalkanoates (PHA) co-culture polymer blend films
Pedagogical Context
Citation
Bioengineering 2020, 7, 34
Publisher
MDPI