Wen Xianghua

Production of citric acid from molasses integrated with in-situ product separation by ion-exchange resin adsorption

Abstract A novel method of citric acid production from beet molasses was developed, in which an anion-exchange resin packed-column was connected to a fermenter for separation of citric acid from fermentation broth. The experimental results indicated that, as compared with conventional batch, the new fermentation techniques increased the citric acid productivity and sugar conversion from 0.338 g/l h and 82.2% to 0.543 g/l h and 94.8%, respectively.

Evaluation of manganese peroxidase (MnP) for its ability to resist the ozonization and thereafter decolorize methyl orange.

The goal of this study was to determine whether ozone can be used to suppress bacterial growth in operating a white rot fungi reactor system. The effects of ozone dose on the activity of manganese peroxidase (MnP) and on the death rate of Escherichia coli were investigated. The results showed that at ozone dose of 0.98 mg/L the MnP activity was not affected after 40 min continuous treatment while the Escherichia coli inactivation rate can reach 99.9% after 30 min; In addition, the MnP that exposed to ozone dose of 1.56 mg/L for 40 min maintained their activity for decolorization of Methyl Orange. After 16 h, the decolorization rate of Methyl Orange was about 41%. These results showed that MnP have the ability to resist to some extent the attack of ozonization, which suggest that ozone might have its potential in suppressing the bacteria contamination in operating the white rot fungi reactor.