Mass Spectrometry Reveals Molecular Structure of Polyhydroxyalkanoates Attained by Bioconversion of Oxidized Polypropylene Waste Fragments

Abstract

This study investigated the molecular structure of the polyhydroxyalkanoate (PHA) produced via a microbiological shake flask experiment utilizing oxidized polypropylene (PP) waste as an additional carbon source. The bacterial strain Cupriavidus necator H16 was selected as it is non-pathogenic, genetically stable, robust, and one of the best known producers of PHA. Making use of PHA oligomers, formed by controlled moderate-temperature degradation induced by carboxylate moieties, by examination of both the parent and fragmentation ions, the ESI-MS/MS analysis revealed the 3-hydroxybutyrate and randomly distributed 3-hydroxyvalerate as well as 3-hydroxyhexanoate repeat units. Thus, the bioconversion of PP solid waste to a value-added product such as PHA tert-polymer was demonstrated.

Bioactive and Functional Oligomers Derived from Natural PHA and Their Synthetic Analogs

“…Moreover, the electrospray ionization multistage mass spectrometry (ESI-MS n ) has been successfully applied for verification of PHA microstructure. By means of these methodologies, the random comonomer arrangements have been confirmed in poly(3-hydroxybutyrate-co-3-hydroxyvalerate), (PHBV), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), (PHBH), copolymers, and recently for PHA with more than two different repeat units [60].…”

Microbial Degradation and Valorization of Plastic Wastes

“…During a period of 312 h, Y. lipolytica 78-003 assimilated more than 80% of the substrate and produced up to 492 mg L −1 lipids mainly composed of C 16 -C 18 unsaturated fatty acids (Mihreteab et al, 2019). Johnston et al (2019) found that R. eutropha H16 could utilize oxidized PP fragments as an additional carbon source to produce PHA in TSB medium.…”

Recent Advances in Sustainable Plastic Upcycling and Biopolymers

“…[ 141,142 ] In addition, PP waste fragments were converted into P(3HB‐ ter ‐3HV‐ ter ‐3HHx) by using R. eutropha H16 as the host strain. [ 143 ] There also has been reports using TPA as the carbon source formed from PET pyrolysis for further production of PHAs. Several bacteria, isolated from the plant processing PET bottle, have been identified as Pseudomonas putida (GO16), Pseudomonas putida (GO19), and Pseudomonas frederiksbergensis GO23.…”