Poly-3-hydroxyalkanoates Produced from <i>Pseudomonas oleovorans</i> Grown with ω-Phenoxyalkanoates

Abstract

Poly-3-hydroxyalkanoates (PHAs) produced by Pseudomonas oleovorans grown solely with 6-phenoxyhexanoate, 8-phenoxyoctanoate, and 11-phenoxyundecanoate were investigated. Weight fractions of PHAs in dry cells were ∼10%, regardless of the carbon substrate used. DSC thermograms of these polymers showed no crystalline melting endotherm. Glass transition temperatures were ∼20 °C, and number-average molecular weights were ∼65 000, with polydispersity indexes of 2.7 for all PHAs. GC/MS analysis showed that 3-hydroxy-5-phenoxypentanoate was the main repeating unit in the PHA produced from 11-phenoxyundecanoate, and 3-hydroxy-4-phenoxybutyrate was the main repeating unit in PHAs produced from 6-phenoxyhexanoate and 8-phenoxyoctanoate.