Article

Dissolved-oxygen-stat fed-batch fermentation of 1,3-dihydroxyacetone from glycerol by Gluconobacter oxydans ZJB09112

Biotechnology and Bioprocess Engineering (Impact Factor: 1.22). 08/2010; 15(4):651-656. DOI: 10.1007/s12257-009-3068-2

ABSTRACT This study investigated the effects of DO concentration on DHA fermentation and of DO-stat fed-batch fermentation using a
pH control strategy, on 1,3-dihydroxyacetone (DHA) production. The results showed that DO-stat fed-batch fermentation with
pH-shift control was the optimal bioprocess for DHA production. DO-stat fed-batch fermentation was carried out at 30% air
saturation, and the culture pH was automatically maintained at pH 6.0 during the first 20 h and then shifted to pH 5.0 until
the end of the fermentation. An optimal DHA concentration of 175.9 ± 6.7 g/L, with a production yield to glycerol of 0.87
± 0.04 g/g, was obtained at 72 h of DO-stat fed-batch fermentation at 30°C in a 15 L fermenter.

Keywords1,3-dihydroxyacetone-
Gluconobacter oxydans
-DO-stat fermentation-glycerol-fed-batch

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