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The study of glycerol-based fermentation and broth downstream by nanofiltration

100%

Gryta M., Markowska-Szczupak A., Grzechulska-Damszel J., Bastrzyk J., Waszak M.

Polish Journal of Chemical Technology

2014

vol. 16

issue 4

117-122

In this work, the glycerol fermentation was carried out using Citrobacter freundii bacteria. The influence of glycerol and metabolites concentrations, and the pH changes on the efficiency of 1,3-propanediol production, during batch and fed-batch processes, was presented. The nanofiltration was used for the separation of obtained post-fermentation solutions. The resulted 1,3-PD solutions were significantly desalted, which may facilitate further downstream processes during 1,3-PD production.

1,3-Propanediol production by Escherichia coli using genes from Citrobacter freundii atcc 8090

75%

Przystałowska H., Zeyland J., Kośmider A., Szalata M., Słomski R., Lipiński D.

issue 3

589-597

Compared with chemical synthesis, fermentation has the advantage of mass production at low cost, and has been used in the production of various industrial chemicals. As a valuable organic compound, 1,3-propanediol (1,3-PDO) has numerous applications in the production of polymers, lubricants, cosmetics and medicines. Here, conversion of glycerol (a renewable substrate and waste from biodiesel production) to 1,3-PDO by E. coli bacterial strain carrying altered glycerol metabolic pathway was investigated. Two gene constructs containing the 1,3-PDO operon from Citrobacter freundii (pCF1 and pCF2) were used to transform the bacteria. The pCF1 gene expression construct contained dhaBCE genes encoding the three subunits of glycerol dehydratase, dhaF encoding the large subunit of the glycerol dehydratase reactivation factor and dhaG encoding the small subunit of the glycerol dehydratase reactivating factor. The pCF2 gene expression construct contained the dhaT gene encoding the 1,3-propanediol dehydrogenase. Expression of the genes cloned in the above constructs was under regulation of the T7lac promoter. RT-PCR, SDS-PAGE analyses and functional tests confirmed that 1,3-PDO synthesis pathway genes were expressed at the RNA and protein levels, and worked flawlessly in the heterologous host. In a batch flask culture, in a short time applied just to identify the 1,3-PDO in a preliminary study, the recombinant E. coli bacteria produced 1.53 g/L of 1,3-PDO, using 21.2 g/L of glycerol in 72 h. In the Sartorius Biostat B Plus reactor, they produced 11.7 g/L of 1,3-PDO using 24.2 g/L of glycerol, attaining an efficiency of 0.58 [mol1,3-PDO/molglycerol].

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1 Acta Biochimica Polonica

1 Polish Journal of Chemical Technology

1 2015

1 2014

1 Bastrzyk J.

1 Gryta M.

1 Grzechulska-Damszel J.

1 Kośmider A.

1 Lipiński D.

1 Markowska-Szczupak A.

1 Przystałowska H.

1 Szalata M.

1 Słomski R.

1 Waszak M.

1 Zeyland J.

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The study of glycerol-based fermentation and broth downstream by nanofiltration

1,3-Propanediol production by Escherichia coli using genes from Citrobacter freundii atcc 8090