Development of High Cell Density Cultivation Strategies for Improved Medium Chain Length Polyhydroxyalkanoate Productivity Using Pseudomonas putida LS46

Development of High Cell Density Cultivation Strategies for Improved Medium Chain Length Polyhydroxyalkanoate Productivity Using Pseudomonas putida LS46

Blog Article

High cell density (HCD) fed-batch cultures are widely perceived as a requisite for high-productivity polyhydroxyalkanoate (PHA) cultivation processes.In this work, a reactive pulse feed strategy (based on real-time CO2 or dissolved oxygen (DO) measurements as feedback variables) was used to control an oxygen-limited fed-batch process for improved productivity of medium chain length (mcl-) PHAs synthesized by Pseudomonas putida LS46.Despite the onset of oxygen limitation half-way through the process (14 h post inoculation), 28.

8 ± 3.9 g L−1 total biomass (with PHA content up to 61 ± 8% cell dry mass) was reliably achieved within 27 h using iphone 14 price chicago octanoic acid as the carbon source in a bench-scale (7 L) bioreactor operated under atmospheric conditions.This resulted in a final volumetric productivity of 0.

66 ± 0.14 g L−1 h−1.Delivering carbon to the bioreactor as a continuous drip feed process (a proactive feeding strategy compared to pulse feeding) made little difference on the final volumetric productivity of 0.

60 ± 0.04 g L−1 h−1.However, the drip feed strategy favored production of non-PHA residual biomass during the growth phase, while pulse feeding favored a higher rate of mcl-PHA synthesis and yield during the storage phase.

Overall, it was shown that the inherent O2-limitation brought about by HCD cultures can be used as a simple and effective control strategy for mcl-PHA synthesis from fatty acids.Furthermore, the pulse feed strategy appears to be a relatively easy and reliable method for rapid optimization of fed-batch processes, particularly when read more using toxic substrates like octanoic acid.