PH-stat fed-batch culture

A pH-stat fed-batch strategy was applied for the culture of transformant Ralstonia eutropha REZ coexpressing the phbC and zwf genes. It was cultivated in a minimal medium followed by feeding 10 g/1 of fructose and valerate to maintain a pH level of 7.0. This strategy resulted in the production of a 60.1% poly(3HB-co-3HV) copolymer and cell mass of 14 g/1. The 3HV monomer composition reached 71.9 mol% [18]. 

Kobayashi G, Tanaka K, Itoh H, Tsuge T, Sonomoto K, IshizaM A (2000) Fermentative production of P(3HB-co-3HV) from propionic add by Alcaligenes eutrophus in fed-batch culture with pH-stat continuous substrate feeding method. Biotechnol Lett 22 1067-1069 Koh LP (2008) Can oil palm plantations be made more hospitable for forest butterflies and birds J Appl Ecol 45 1002-1009... 

Suzuki T, Yamane T, Shimizu S. Mass production of thiostrepton by fed-batch culture of Strepcomyces laurentii with pH-stat modal feeding of mulci-subsirate. AppI Microbiol Biotech-nol 1987 25 526-531. 

Fed-batch culture with pH-stat continuous C. saccharoperbutylacetonicum Nl-4 Glucose + butyric add (5) 16 Tashiro et al. (2004)... 

Tashiro, Y, Takeda, K., Kobayashi, G., Sonomoto, K., Ishizaki, A., Yoshino, S., 2004. High butanol production by Clostridium saccharoperhutylacetonicum Nl-4 in fed-batch culture with pH-Stat continuous butyric acid and glucose feeding method. Journal of Bioscience and Bioengineering 98 (4), 263-268. 

When an NHg solution is used as a nitrogen source of fermentation, the consumption of NHg decreases the pH of the culture broth. A pH stat control utilizes the pH change as a process variable where the NHg addition is manipulated so as to keep the pH value constant during fermentation. The pH stat is often employed in a fed-batch cultivation of industrial glutamic acid production (high NHg consuming fermentation) using molasses as a feedstock. 

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