Bioconversion of fumarate to succinate using glycerol as a carbon source

In this study, a facultative bacterium that converts fumarate to succinate at a high yield was isolated. The yield of bioconversion was enhanced about 1.2 times by addition of glucose into culture medium at an initial concent ration of 6 g/L. When the initial cell density was high (2 g/L), the succin ate produced at pH 7.0 for initial fumarate concentrations of 30, 50, 80, a nd 100 g/L were 29.3, 40.9, 63.6, and 82.5 g/L, respectively, showing an in crease with the initial fumarate concentration. The high yield of 96.8%/mol e of fumarate in just 4 h was obtained at the initial fumarate concentratio n of 30 g/L. Comparing these values to those obtained with low cell culture (0.2 g/L), we found that the amount of succinate produced was similar, but the production rate in the high cell culture was about three times higher than was the case in the low cell culture. This strain converted fumarate t o succinate at a rate of 3.5 g/L.h under the sparge of CO2.