Type

Journal Article

Authors

Kevin E O'Connor
Shane T Kenny
Aisling R Hume
Dragana Mitic
Gearoid F Duane
Eoin Casey
Jasmina Nikodinovic-Runic

Subjects

Engineering

Topics
phase transitions conversion biomass cell growth chain length phase process improvement process analysis

Process analysis of the conversion of styrene to biomass and medium chain length polyhydroxyalkanoate in a two-phase bioreactor. (2011)

Abstract The improvement and modeling of a process for the supply of the volatile aromatic hydrocarbon, styrene, to a fermentor for increased biomass production of the medium chain length polyhydroxyalkanoate (mcl-PHA) accumulating bacterium Pseudomonas putida CA-3 was investigated. Fed-batch experiments were undertaken using different methods to provide the styrene. Initial experiments where styrene was supplied as a liquid to the bioreactor had detrimental effects on cell growth and inhibited PHA polymer accumulation. By changing the feed of gaseous styrene to liquid styrene through the air sparger a 5.4-fold increase in cell dry-weight was achieved (total of 10.56 g L(-1) ) which corresponds to a fourfold improvement in PHA production (3.36 g L(-1) ) compared to previous studies performed in our laboratory (0.82 g L(-1) ). In addition this final improved feeding strategy reduced the release of styrene from the fermentor 50-fold compared to initial experiments (0.12 mL total styrene released per 48 h run). An unstructured kinetic model was developed to describe cell growth along with substrate and oxygen utilization. The formation of dispersed gas (air) and liquid (styrene) phases in the medium and the transfer of styrene between the aqueous and dispersed liquid droplet phases was also modeled. The model provided a detailed description of these phase transitions and helped explain how the feeding strategy led to improved process performance in terms of final biomass levels. It also highlighted the key factors to be considered during further process improvement. Biotechnol. Bioeng. © 2011 Wiley Periodicals, Inc.
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Full list of authors on original publication

Kevin E O'Connor, Shane T Kenny, Aisling R Hume, Dragana Mitic, Gearoid F Duane, Eoin Casey, Jasmina Nikodinovic-Runic

Experts in our system

1
Kevin E O'Connor
University College Dublin
Total Publications: 52
 
2
Shane T Kenny
University College Dublin
Total Publications: 15
 
3
Eoin Casey
University College Dublin
Total Publications: 68
 
4
Jasmina Nikodinovic-Runic
University College Dublin
Total Publications: 19