Abstract:

In order to obtain high glutathione (GSH) yield and dry cell weight, fed-batch fermentation in a 5 L fermentor was adopted for glutathione production by a DL-ethionine, zinc chloride-resistant mutant of Saccharomyces cerevisiae. Strategy for fed-batch feeding of glucose at an initial concentration of 20 g/L was investigated. Results showed that the fed-batch feeding strategy of adding 22, 24, 24, 24, 24 g/L and 22 g/L glucose at intervals of 3 h from 12 to 27 h of fermentation resulted in 72.49 mg/L GSH concentration and 28.52 g/L dry cell weight, which was 2.86 times and 4.93 times as high as those obtained by single batch fermentation. This meant that fed-batch fermentation could remarkably promote strain growth and enhance GSH production.

Key words: fed-batch, fermentation, glutathione