Improvement of the conversion of polystyrene to polyhydroxyalkanoate through the manipulation of the microbial aspect of the process: a nitrogen feeding strategy for bacterial cells in a stirred tank reactor.

Pseudomonas putida CA-3 has been shown to accumulate the biodegradable plastic polyhydroxyalkanoate (PHA) when fed styrene or polystyrene pyrolysis oil as the sole carbon and energy source under nitrogen limiting growth conditions (67 mg nitrogen per litre at time 0). Batch fermentation of P. putida CA-3 grown on styrene or polystyrene pyrolysis oil in a stirred tank reactor yields PHA at 30% of the cell dry weight (CDW).

Microbial degradation of styrene: biochemistry, molecular genetics, and perspectives for biotechnological applications.

Large quantities of the potentially toxic compound styrene are produced and used annually by the petrochemical and polymer-processing industries. It is as a direct consequence of this that significant volumes of styrene are released into the environment in both the liquid and the gaseous forms. Styrene and its metabolites are known to have serious negative effects on human health and therefore, strategies to prevent its release, remove it from the environment, and understand its route of degradation were the subject of much research.

A two step chemo-biotechnological conversion of polystyrene to a biodegradable thermoplastic.

A novel approach to the recycling of polystyrene is reported here; polystyrene is converted to a biodegradable plastic, namely polyhydroxyalkanoate (PHA). This unique combinatorial approach involves the pyrolysis of polystyrene to styrene oil, followed by the bacterial conversion of the styrene oil to PHA by Pseudomonas putida CA-3 (NCIMB 41162). The pyrolysis (520 degrees C) of polystyrene in a fluidized bed reactor (Quartz sand (0.

Induction and quantification of phenylacyl-CoA ligase enzyme activities in Pseudomonas putida CA-3 grown on aromatic carboxylic acids.

Three phenylacyl-CoA ligase activities were detected in extracts of Pseudomonas putida CA-3 cells grown with a variety of aromatic carboxylic acids. The three phenylacyl-CoA enzyme activities measured were phenylpropyl-CoA ligase (acting on both phenylpropanoic acid and cinnamic acid), a phenylacetyl-CoA ligase, and a medium chain length phenylalkanoyl-CoA ligase acting on aromatic substrates with 5 or more carbons in the acyl moiety. The rate of each enzyme activity detected in extracts of P.

Accumulation of polyhydroxyalkanoate from styrene and phenylacetic acid by Pseudomonas putida CA-3.

Pseudomonas putida CA-3 is capable of converting the aromatic hydrocarbon styrene, its metabolite phenylacetic acid, and glucose into polyhydroxyalkanoate (PHA) when a limiting concentration of nitrogen (as sodium ammonium phosphate) is supplied to the growth medium. PHA accumulation occurs to a low level when the nitrogen concentration drops below 26.8 mg/liter and increases rapidly once the nitrogen is no longer detectable in the growth medium.

Bacterial synthesis of polyhydroxyalkanoates containing aromatic and aliphatic monomers by Pseudomonas putida CA-3.

Pseudomonas putida CA-3 has the ability to accumulate to high levels unique polyhydroxyalkanoate (PHA) heteropolymers composed of aromatic and aliphatic monomers. The majority of monomers are aromatic making up 98% of the polymer. (R)-3-hydroxyphenylvalerate and (R)-3-hydroxyphenylhexanoate are the most abundant monomers found in polymers accumulated from phenylalkanoic acids with an uneven and even number of carbons on the acyl side chain respectively.