Volatile fatty acids influence on the structure of microbial communities producing PHAs.

Polyhydroxyalkanoates (PHAs) can be produced by microorganisms and are a biodegradable alternative to fossil-fuel based plastics. Currently, the focus is on reducing production costs by exploring alternative substrates for PHAs production, and on producing copolymers which are less brittle than monomers. Accordingly, this study used a substrate consisting of wastewater from waste-glycerol fermentation, supplemented with different amounts of acetic and propionic acids.

Mcl-PHAs produced by Pseudomonas sp. Gl01 using fed-batch cultivation with waste rapeseed oil as carbon source.

The present study describes medium-chain-length polyhydroxyalkanoates (mcl-PHAs) production by the Pseudomonas Gl01 strain isolated from mixed microbial communities utilized for PHAs synthesis. A two-step fedbatch fermentation was conducted with glucose and waste rapeseed oil as the main carbon source for obtaining cell growth and mcl-PHAs accumulation, respectively. The results show that the Pseudomonas Gl01 strain is capable of growing and accumulating mcl-PHAs using a waste oily carbon source.

The influence of nitrogen limitation on mcl-PHA synthesis by two newly isolated strains of Pseudomonas sp.

The nucleotide composition of key enzymes involved in medium-chain-length polyhydroxyalkanoates (mcl-PHA) synthesis was analyzed in two newly isolated strains of Pseudomonas. The isolated strains were tested for their abilities to synthesize polyhydroxyalkanoates using three different substrates as a carbon source: sodium octanoate, oleic acid, and sodium gluconate. Both analyzed strains were able to accumulate mcl-PHA in a range from 2.